diff --git a/content/base/public/nsContentUtils.h b/content/base/public/nsContentUtils.h
index 5f5c212b1490..9797b72cfce6 100644
--- a/content/base/public/nsContentUtils.h
+++ b/content/base/public/nsContentUtils.h
@@ -99,7 +99,6 @@ class nsIRunnable;
 class nsIInterfaceRequestor;
 template<class E> class nsCOMArray;
 class nsIPref;
-class nsVoidArray;
 struct JSRuntime;
 class nsICaseConversion;
 class nsIUGenCategory;
@@ -212,12 +211,9 @@ public:
   /*
    * This method fills the |aArray| with all ancestor nodes of |aNode|
    * including |aNode| at the zero index.
-   *
-   * These elements were |nsIDOMNode*|s before casting to |void*| and must
-   * be cast back to |nsIDOMNode*| on usage, or bad things will happen.
    */
   static nsresult GetAncestors(nsIDOMNode* aNode,
-                               nsVoidArray* aArray);
+                               nsTArray<nsIDOMNode*>* aArray);
 
   /*
    * This method fills |aAncestorNodes| with all ancestor nodes of |aNode|
@@ -225,16 +221,12 @@ public:
    * For each ancestor, there is a corresponding element in |aAncestorOffsets|
    * which is the IndexOf the child in relation to its parent.
    *
-   * The elements of |aAncestorNodes| were |nsIContent*|s before casting to
-   * |void*| and must be cast back to |nsIContent*| on usage, or bad things
-   * will happen.
-   *
    * This method just sucks.
    */
   static nsresult GetAncestorsAndOffsets(nsIDOMNode* aNode,
                                          PRInt32 aOffset,
-                                         nsVoidArray* aAncestorNodes,
-                                         nsVoidArray* aAncestorOffsets);
+                                         nsTArray<nsIContent*>* aAncestorNodes,
+                                         nsTArray<PRInt32>* aAncestorOffsets);
 
   /*
    * The out parameter, |aCommonAncestor| will be the closest node, if any,
@@ -837,7 +829,7 @@ public:
   static nsresult ReleasePtrOnShutdown(nsISupports** aSupportsPtr) {
     NS_ASSERTION(aSupportsPtr, "Expect to crash!");
     NS_ASSERTION(*aSupportsPtr, "Expect to crash!");
-    return sPtrsToPtrsToRelease->AppendElement(aSupportsPtr) ? NS_OK :
+    return sPtrsToPtrsToRelease->AppendElement(aSupportsPtr) != nsnull ? NS_OK :
       NS_ERROR_OUT_OF_MEMORY;
   }
 
@@ -1463,7 +1455,7 @@ private:
   static nsIUGenCategory* sGenCat;
 
   // Holds pointers to nsISupports* that should be released at shutdown
-  static nsVoidArray* sPtrsToPtrsToRelease;
+  static nsTArray<nsISupports**>* sPtrsToPtrsToRelease;
 
   static nsIScriptRuntime* sScriptRuntimes[NS_STID_ARRAY_UBOUND];
   static PRInt32 sScriptRootCount[NS_STID_ARRAY_UBOUND];
diff --git a/content/base/public/nsIContent.h b/content/base/public/nsIContent.h
index 0eafd97dc012..61f9d024a12c 100644
--- a/content/base/public/nsIContent.h
+++ b/content/base/public/nsIContent.h
@@ -48,7 +48,6 @@
 class nsIAtom;
 class nsIDocument;
 class nsPresContext;
-class nsVoidArray;
 class nsIDOMEvent;
 class nsIContent;
 class nsIEventListenerManager;
diff --git a/content/base/public/nsINode.h b/content/base/public/nsINode.h
index 48c934d0f81c..516e590e1fa1 100644
--- a/content/base/public/nsINode.h
+++ b/content/base/public/nsINode.h
@@ -59,7 +59,6 @@ class nsEventChainPreVisitor;
 class nsEventChainPostVisitor;
 class nsIEventListenerManager;
 class nsIPrincipal;
-class nsVoidArray;
 class nsIMutationObserver;
 class nsChildContentList;
 class nsNodeWeakReference;
diff --git a/content/base/public/nsXMLNameSpaceMap.h b/content/base/public/nsXMLNameSpaceMap.h
index 411a2d5f2ca9..b3b0c3c035e6 100644
--- a/content/base/public/nsXMLNameSpaceMap.h
+++ b/content/base/public/nsXMLNameSpaceMap.h
@@ -39,9 +39,11 @@
 #ifndef nsXMLNameSpaceMap_h_
 #define nsXMLNameSpaceMap_h_
 
-#include "nsVoidArray.h"
+#include "nsString.h"
+#include "nsTArray.h"
 
 class nsIAtom;
+class nsNameSpaceEntry;
 
 /**
  * nsXMLNameSpaceMap contains a set of prefixes which are mapped onto
@@ -94,7 +96,7 @@ public:
 private:
   nsXMLNameSpaceMap() NS_HIDDEN;  // use Create() to create new instances
 
-  nsVoidArray mNameSpaces;
+  nsTArray<nsNameSpaceEntry*> mNameSpaces;
 };
 
 #endif
diff --git a/content/base/src/nsContentIterator.cpp b/content/base/src/nsContentIterator.cpp
index cba70fb6fe33..8eabc626cfd4 100644
--- a/content/base/src/nsContentIterator.cpp
+++ b/content/base/src/nsContentIterator.cpp
@@ -47,7 +47,7 @@
 #include "nsIComponentManager.h"
 #include "nsContentCID.h"
 #include "nsLayoutCID.h"
-#include "nsVoidArray.h"
+#include "nsTArray.h"
 #include "nsContentUtils.h"
 #include "nsINode.h"
 
@@ -155,19 +155,19 @@ public:
 
 protected:
 
-  nsINode* GetDeepFirstChild(nsINode *aRoot, nsVoidArray *aIndexes);
-  nsINode* GetDeepLastChild(nsINode *aRoot, nsVoidArray *aIndexes);
+  nsINode* GetDeepFirstChild(nsINode *aRoot, nsTArray<PRInt32> *aIndexes);
+  nsINode* GetDeepLastChild(nsINode *aRoot, nsTArray<PRInt32> *aIndexes);
 
   // Get the next sibling of aNode.  Note that this will generally return null
   // if aNode happens not to be a content node.  That's OK.
-  nsINode* GetNextSibling(nsINode *aNode, nsVoidArray *aIndexes);
+  nsINode* GetNextSibling(nsINode *aNode, nsTArray<PRInt32> *aIndexes);
 
   // Get the prev sibling of aNode.  Note that this will generally return null
   // if aNode happens not to be a content node.  That's OK.
-  nsINode* GetPrevSibling(nsINode *aNode, nsVoidArray *aIndexes);
+  nsINode* GetPrevSibling(nsINode *aNode, nsTArray<PRInt32> *aIndexes);
 
-  nsINode* NextNode(nsINode *aNode, nsVoidArray *aIndexes);
-  nsINode* PrevNode(nsINode *aNode, nsVoidArray *aIndexes);
+  nsINode* NextNode(nsINode *aNode, nsTArray<PRInt32> *aIndexes);
+  nsINode* PrevNode(nsINode *aNode, nsTArray<PRInt32> *aIndexes);
 
   // WARNING: This function is expensive
   nsresult RebuildIndexStack();
@@ -180,7 +180,7 @@ protected:
   nsCOMPtr<nsINode> mCommonParent;
 
   // used by nsContentIterator to cache indices
-  nsAutoVoidArray mIndexes;
+  nsAutoTArray<PRInt32, 8> mIndexes;
 
   // used by nsSubtreeIterator to cache indices.  Why put them in the base class?
   // Because otherwise I have to duplicate the routines GetNextSibling etc across both classes,
@@ -539,7 +539,7 @@ nsresult nsContentIterator::RebuildIndexStack()
     if (!parent)
       return NS_ERROR_FAILURE;
   
-    mIndexes.InsertElementAt(NS_INT32_TO_PTR(parent->IndexOf(current)), 0);
+    mIndexes.InsertElementAt(0, parent->IndexOf(current));
 
     current = parent;
   }
@@ -558,7 +558,8 @@ nsContentIterator::MakeEmpty()
 }
 
 nsINode*
-nsContentIterator::GetDeepFirstChild(nsINode *aRoot, nsVoidArray *aIndexes)
+nsContentIterator::GetDeepFirstChild(nsINode *aRoot,
+                                     nsTArray<PRInt32> *aIndexes)
 {
   if (!aRoot) {
     return nsnull;
@@ -572,7 +573,7 @@ nsContentIterator::GetDeepFirstChild(nsINode *aRoot, nsVoidArray *aIndexes)
     if (aIndexes)
     {
       // Add this node to the stack of indexes
-      aIndexes->AppendElement(NS_INT32_TO_PTR(0));
+      aIndexes->AppendElement(0);
     }
     n = nChild;
     nChild = n->GetChildAt(0);
@@ -582,7 +583,7 @@ nsContentIterator::GetDeepFirstChild(nsINode *aRoot, nsVoidArray *aIndexes)
 }
 
 nsINode*
-nsContentIterator::GetDeepLastChild(nsINode *aRoot, nsVoidArray *aIndexes)
+nsContentIterator::GetDeepLastChild(nsINode *aRoot, nsTArray<PRInt32> *aIndexes)
 {
   if (!aRoot) {
     return nsnull;
@@ -600,7 +601,7 @@ nsContentIterator::GetDeepLastChild(nsINode *aRoot, nsVoidArray *aIndexes)
     if (aIndexes)
     {
       // Add this node to the stack of indexes
-      aIndexes->AppendElement(NS_INT32_TO_PTR(numChildren));
+      aIndexes->AppendElement(numChildren);
     }
     numChildren = nChild->GetChildCount();
     n = nChild;
@@ -614,7 +615,7 @@ nsContentIterator::GetDeepLastChild(nsINode *aRoot, nsVoidArray *aIndexes)
 // Get the next sibling, or parents next sibling, or grandpa's next sibling...
 nsINode *
 nsContentIterator::GetNextSibling(nsINode *aNode, 
-                                  nsVoidArray *aIndexes)
+                                  nsTArray<PRInt32> *aIndexes)
 {
   if (!aNode) 
     return nsnull;
@@ -623,13 +624,14 @@ nsContentIterator::GetNextSibling(nsINode *aNode,
   if (!parent)
     return nsnull;
 
-  PRInt32 indx;
+  PRInt32 indx = 0;
 
-  if (aIndexes)
+  NS_ASSERTION(!aIndexes || !aIndexes->IsEmpty(),
+               "ContentIterator stack underflow");
+  if (aIndexes && !aIndexes->IsEmpty())
   {
-    NS_ASSERTION(aIndexes->Count() > 0, "ContentIterator stack underflow");
     // use the last entry on the Indexes array for the current index
-    indx = NS_PTR_TO_INT32((*aIndexes)[aIndexes->Count()-1]);
+    indx = (*aIndexes)[aIndexes->Length()-1];
   }
   else
     indx = mCachedIndex;
@@ -648,9 +650,9 @@ nsContentIterator::GetNextSibling(nsINode *aNode,
   if ((sib = parent->GetChildAt(++indx)))
   {
     // update index cache
-    if (aIndexes)
+    if (aIndexes && !aIndexes->IsEmpty())
     {
-      aIndexes->ReplaceElementAt(NS_INT32_TO_PTR(indx),aIndexes->Count()-1);
+      aIndexes->ElementAt(aIndexes->Length()-1) = indx;
     }
     else mCachedIndex = indx;
   }
@@ -663,8 +665,8 @@ nsContentIterator::GetNextSibling(nsINode *aNode,
         // pop node off the stack, go up one level and return parent or fail.
         // Don't leave the index empty, especially if we're
         // returning NULL.  This confuses other parts of the code.
-        if (aIndexes->Count() > 1)
-          aIndexes->RemoveElementAt(aIndexes->Count()-1);
+        if (aIndexes->Length() > 1)
+          aIndexes->RemoveElementAt(aIndexes->Length()-1);
       }
     }
 
@@ -678,7 +680,7 @@ nsContentIterator::GetNextSibling(nsINode *aNode,
 // Get the prev sibling, or parents prev sibling, or grandpa's prev sibling...
 nsINode*
 nsContentIterator::GetPrevSibling(nsINode *aNode, 
-                                  nsVoidArray *aIndexes)
+                                  nsTArray<PRInt32> *aIndexes)
 {
   if (!aNode)
     return nsnull;
@@ -687,13 +689,14 @@ nsContentIterator::GetPrevSibling(nsINode *aNode,
   if (!parent)
     return nsnull;
 
-  PRInt32 indx;
+  PRInt32 indx = 0;
 
-  if (aIndexes)
+  NS_ASSERTION(!aIndexes || !aIndexes->IsEmpty(),
+               "ContentIterator stack underflow");
+  if (aIndexes && !aIndexes->IsEmpty())
   {
-    NS_ASSERTION(aIndexes->Count() > 0, "ContentIterator stack underflow");
     // use the last entry on the Indexes array for the current index
-    indx = NS_PTR_TO_INT32((*aIndexes)[aIndexes->Count()-1]);
+    indx = (*aIndexes)[aIndexes->Length()-1];
   }
   else
     indx = mCachedIndex;
@@ -711,18 +714,18 @@ nsContentIterator::GetPrevSibling(nsINode *aNode,
   if (indx > 0 && (sib = parent->GetChildAt(--indx)))
   {
     // update index cache
-    if (aIndexes)
+    if (aIndexes && !aIndexes->IsEmpty())
     {
-      aIndexes->ReplaceElementAt(NS_INT32_TO_PTR(indx),aIndexes->Count()-1);
+      aIndexes->ElementAt(aIndexes->Length()-1) = indx;
     }
     else mCachedIndex = indx;
   }
   else if (parent != mCommonParent)
   {
-    if (aIndexes)
+    if (aIndexes && !aIndexes->IsEmpty())
     {
       // pop node off the stack, go up one level and try again.
-      aIndexes->RemoveElementAt(aIndexes->Count()-1);
+      aIndexes->RemoveElementAt(aIndexes->Length()-1);
     }
     return GetPrevSibling(parent, aIndexes);
   }
@@ -731,7 +734,7 @@ nsContentIterator::GetPrevSibling(nsINode *aNode,
 }
 
 nsINode*
-nsContentIterator::NextNode(nsINode *aNode, nsVoidArray *aIndexes)
+nsContentIterator::NextNode(nsINode *aNode, nsTArray<PRInt32> *aIndexes)
 {
   nsINode *n = aNode;
   nsINode *nextNode = nsnull;
@@ -747,7 +750,7 @@ nsContentIterator::NextNode(nsINode *aNode, nsVoidArray *aIndexes)
       if (aIndexes)
       {
         // push an entry on the index stack
-        aIndexes->AppendElement(NS_INT32_TO_PTR(0));
+        aIndexes->AppendElement(0);
       }
       else mCachedIndex = 0;
       
@@ -761,14 +764,15 @@ nsContentIterator::NextNode(nsINode *aNode, nsVoidArray *aIndexes)
   {
     nsINode *parent = n->GetNodeParent();
     nsINode *nSibling = nsnull;
-    PRInt32 indx;
+    PRInt32 indx = 0;
 
     // get the cached index
-    if (aIndexes)
+    NS_ASSERTION(!aIndexes || !aIndexes->IsEmpty(),
+                 "ContentIterator stack underflow");
+    if (aIndexes && !aIndexes->IsEmpty())
     {
-      NS_ASSERTION(aIndexes->Count() > 0, "ContentIterator stack underflow");
       // use the last entry on the Indexes array for the current index
-      indx = NS_PTR_TO_INT32((*aIndexes)[aIndexes->Count()-1]);
+      indx = (*aIndexes)[aIndexes->Length()-1];
     }
     else indx = mCachedIndex;
 
@@ -788,10 +792,10 @@ nsContentIterator::NextNode(nsINode *aNode, nsVoidArray *aIndexes)
     if (nSibling)
     {
       // update cache
-      if (aIndexes)
+      if (aIndexes && !aIndexes->IsEmpty())
       {
         // replace an entry on the index stack
-        aIndexes->ReplaceElementAt(NS_INT32_TO_PTR(indx),aIndexes->Count()-1);
+        aIndexes->ElementAt(aIndexes->Length()-1) = indx;
       }
       else mCachedIndex = indx;
       
@@ -806,8 +810,8 @@ nsContentIterator::NextNode(nsINode *aNode, nsVoidArray *aIndexes)
       // pop an entry off the index stack
       // Don't leave the index empty, especially if we're
       // returning NULL.  This confuses other parts of the code.
-      if (aIndexes->Count() > 1)
-        aIndexes->RemoveElementAt(aIndexes->Count()-1);
+      if (aIndexes->Length() > 1)
+        aIndexes->RemoveElementAt(aIndexes->Length()-1);
     }
     else mCachedIndex = 0;   // this might be wrong, but we are better off guessing
     nextNode = parent;
@@ -817,7 +821,7 @@ nsContentIterator::NextNode(nsINode *aNode, nsVoidArray *aIndexes)
 }
 
 nsINode*
-nsContentIterator::PrevNode(nsINode *aNode, nsVoidArray *aIndexes)
+nsContentIterator::PrevNode(nsINode *aNode, nsTArray<PRInt32> *aIndexes)
 {
   nsINode *prevNode = nsnull;
   nsINode *n = aNode;
@@ -826,14 +830,15 @@ nsContentIterator::PrevNode(nsINode *aNode, nsVoidArray *aIndexes)
   {
     nsINode *parent = n->GetNodeParent();
     nsINode *nSibling = nsnull;
-    PRInt32 indx;
+    PRInt32 indx = 0;
 
     // get the cached index
-    if (aIndexes)
+    NS_ASSERTION(!aIndexes || !aIndexes->IsEmpty(),
+                 "ContentIterator stack underflow");
+    if (aIndexes && !aIndexes->IsEmpty())
     {
-      NS_ASSERTION(aIndexes->Count() > 0, "ContentIterator stack underflow");
       // use the last entry on the Indexes array for the current index
-      indx = NS_PTR_TO_INT32((*aIndexes)[aIndexes->Count()-1]);
+      indx = (*aIndexes)[aIndexes->Length()-1];
     }
     else indx = mCachedIndex;
 
@@ -853,10 +858,10 @@ nsContentIterator::PrevNode(nsINode *aNode, nsVoidArray *aIndexes)
     if (indx && (nSibling = parent->GetChildAt(--indx)))
     {
       // update cache
-      if (aIndexes)
+      if (aIndexes && !aIndexes->IsEmpty())
       {
         // replace an entry on the index stack
-        aIndexes->ReplaceElementAt(NS_INT32_TO_PTR(indx),aIndexes->Count()-1);
+        aIndexes->ElementAt(aIndexes->Length()-1) = indx;
       }
       else mCachedIndex = indx;
       
@@ -866,10 +871,10 @@ nsContentIterator::PrevNode(nsINode *aNode, nsVoidArray *aIndexes)
   
     // else it's the parent
     // update cache
-    if (aIndexes)
+    if (aIndexes && !aIndexes->IsEmpty())
     {
       // pop an entry off the index stack
-      aIndexes->RemoveElementAt(aIndexes->Count()-1);
+      aIndexes->RemoveElementAt(aIndexes->Length()-1);
     }
     else mCachedIndex = 0;   // this might be wrong, but we are better off guessing
     prevNode = parent;
@@ -887,7 +892,7 @@ nsContentIterator::PrevNode(nsINode *aNode, nsVoidArray *aIndexes)
       if (aIndexes)
       {
         // push an entry on the index stack
-        aIndexes->AppendElement(NS_INT32_TO_PTR(numChildren));
+        aIndexes->AppendElement(numChildren);
       }
       else mCachedIndex = numChildren;
       
@@ -1043,8 +1048,8 @@ nsContentIterator::PositionAt(nsINode* aCurNode)
 
   // We can be at ANY node in the sequence.
   // Need to regenerate the array of indexes back to the root or common parent!
-  nsAutoVoidArray      oldParentStack;
-  nsAutoVoidArray      newIndexes;
+  nsAutoTArray<nsINode*, 8>     oldParentStack;
+  nsAutoTArray<PRInt32, 8>      newIndexes;
 
   // Get a list of the parents up to the root, then compare the new node
   // with entries in that array until we find a match (lowest common
@@ -1055,17 +1060,17 @@ nsContentIterator::PositionAt(nsINode* aCurNode)
 
   // we know the depth we're down (though we may not have started at the
   // top).
-  if (!oldParentStack.SizeTo(mIndexes.Count()+1))
+  if (!oldParentStack.SetCapacity(mIndexes.Length()+1))
     return NS_ERROR_FAILURE;
 
-  // We want to loop mIndexes.Count() + 1 times here, because we want to make
+  // We want to loop mIndexes.Length() + 1 times here, because we want to make
   // sure we include mCommonParent in the oldParentStack, for use in the next
   // for loop, and mIndexes only has entries for nodes from tempNode up through
   // an ancestor of tempNode that's a child of mCommonParent.
-  for (PRInt32 i = mIndexes.Count()+1; i > 0 && tempNode; i--)
+  for (PRInt32 i = mIndexes.Length()+1; i > 0 && tempNode; i--)
   {
     // Insert at head since we're walking up
-    oldParentStack.InsertElementAt(tempNode,0);
+    oldParentStack.InsertElementAt(0, tempNode);
 
     nsINode *parent = tempNode->GetNodeParent();
 
@@ -1076,8 +1081,8 @@ nsContentIterator::PositionAt(nsINode* aCurNode)
     {
       // The position was moved to a parent of the current position. 
       // All we need to do is drop some indexes.  Shortcut here.
-      mIndexes.RemoveElementsAt(mIndexes.Count() - oldParentStack.Count(),
-                                oldParentStack.Count());
+      mIndexes.RemoveElementsAt(mIndexes.Length() - oldParentStack.Length(),
+                                oldParentStack.Length());
       mIsDone = PR_FALSE;
       return NS_OK;
     }
@@ -1095,7 +1100,7 @@ nsContentIterator::PositionAt(nsINode* aCurNode)
     PRInt32 indx = parent->IndexOf(newCurNode);
 
     // insert at the head!
-    newIndexes.InsertElementAt(NS_INT32_TO_PTR(indx),0);
+    newIndexes.InsertElementAt(0, indx);
 
     // look to see if the parent is in the stack
     indx = oldParentStack.IndexOf(parent);
@@ -1103,12 +1108,12 @@ nsContentIterator::PositionAt(nsINode* aCurNode)
     {
       // ok, the parent IS on the old stack!  Rework things.
       // we want newIndexes to replace all nodes equal to or below the match
-      // Note that index oldParentStack.Count()-1 is the last node, which is
+      // Note that index oldParentStack.Length()-1 is the last node, which is
       // one BELOW the last index in the mIndexes stack.  In other words, we
       // want to remove elements starting at index (indx+1).
-      PRInt32 numToDrop = oldParentStack.Count()-(1+indx);
+      PRInt32 numToDrop = oldParentStack.Length()-(1+indx);
       if (numToDrop > 0)
-        mIndexes.RemoveElementsAt(mIndexes.Count() - numToDrop,numToDrop);
+        mIndexes.RemoveElementsAt(mIndexes.Length() - numToDrop, numToDrop);
       mIndexes.AppendElements(newIndexes);
 
       break;
@@ -1190,12 +1195,12 @@ protected:
   nsCOMPtr<nsIDOMRange> mRange;
   // these arrays all typically are used and have elements
 #if 0
-  nsAutoVoidArray mStartNodes;
-  nsAutoVoidArray mStartOffsets;
+  nsAutoTArray<nsIContent*, 8> mStartNodes;
+  nsAutoTArray<PRInt32, 8>     mStartOffsets;
 #endif
 
-  nsAutoVoidArray mEndNodes;
-  nsAutoVoidArray mEndOffsets;
+  nsAutoTArray<nsIContent*, 8> mEndNodes;
+  nsAutoTArray<PRInt32, 8>     mEndOffsets;
 };
 
 nsresult NS_NewContentSubtreeIterator(nsIContentIterator** aInstancePtrResult);
diff --git a/content/base/src/nsContentUtils.cpp b/content/base/src/nsContentUtils.cpp
index e3e97b8444a4..a857ff542da9 100644
--- a/content/base/src/nsContentUtils.cpp
+++ b/content/base/src/nsContentUtils.cpp
@@ -204,7 +204,7 @@ nsILineBreaker *nsContentUtils::sLineBreaker;
 nsIWordBreaker *nsContentUtils::sWordBreaker;
 nsICaseConversion *nsContentUtils::sCaseConv;
 nsIUGenCategory *nsContentUtils::sGenCat;
-nsVoidArray *nsContentUtils::sPtrsToPtrsToRelease;
+nsTArray<nsISupports**> *nsContentUtils::sPtrsToPtrsToRelease;
 nsIScriptRuntime *nsContentUtils::sScriptRuntimes[NS_STID_ARRAY_UBOUND];
 PRInt32 nsContentUtils::sScriptRootCount[NS_STID_ARRAY_UBOUND];
 PRUint32 nsContentUtils::sJSGCThingRootCount;
@@ -328,7 +328,7 @@ nsContentUtils::Init()
     sImgLoader = nsnull;
   }
 
-  sPtrsToPtrsToRelease = new nsVoidArray();
+  sPtrsToPtrsToRelease = new nsTArray<nsISupports**>();
   if (!sPtrsToPtrsToRelease) {
     return NS_ERROR_OUT_OF_MEMORY;
   }
@@ -865,8 +865,8 @@ nsContentUtils::Shutdown()
 
   NS_IF_RELEASE(sContentPolicyService);
   sTriedToGetContentPolicy = PR_FALSE;
-  PRInt32 i;
-  for (i = 0; i < PRInt32(PropertiesFile_COUNT); ++i)
+  PRUint32 i;
+  for (i = 0; i < PropertiesFile_COUNT; ++i)
     NS_IF_RELEASE(sStringBundles[i]);
   NS_IF_RELEASE(sStringBundleService);
   NS_IF_RELEASE(sConsoleService);
@@ -896,9 +896,8 @@ nsContentUtils::Shutdown()
   sEventTable = nsnull;
 
   if (sPtrsToPtrsToRelease) {
-    for (i = 0; i < sPtrsToPtrsToRelease->Count(); ++i) {
-      nsISupports** ptrToPtr =
-        static_cast<nsISupports**>(sPtrsToPtrsToRelease->ElementAt(i));
+    for (i = 0; i < sPtrsToPtrsToRelease->Length(); ++i) {
+      nsISupports** ptrToPtr = sPtrsToPtrsToRelease->ElementAt(i);
       NS_RELEASE(*ptrToPtr);
     }
     delete sPtrsToPtrsToRelease;
@@ -1400,7 +1399,7 @@ nsContentUtils::ContentIsDescendantOf(nsINode* aPossibleDescendant,
 // static
 nsresult
 nsContentUtils::GetAncestors(nsIDOMNode* aNode,
-                             nsVoidArray* aArray)
+                             nsTArray<nsIDOMNode*>* aArray)
 {
   NS_ENSURE_ARG_POINTER(aNode);
 
@@ -1420,8 +1419,8 @@ nsContentUtils::GetAncestors(nsIDOMNode* aNode,
 nsresult
 nsContentUtils::GetAncestorsAndOffsets(nsIDOMNode* aNode,
                                        PRInt32 aOffset,
-                                       nsVoidArray* aAncestorNodes,
-                                       nsVoidArray* aAncestorOffsets)
+                                       nsTArray<nsIContent*>* aAncestorNodes,
+                                       nsTArray<PRInt32>* aAncestorOffsets)
 {
   NS_ENSURE_ARG_POINTER(aNode);
 
@@ -1431,26 +1430,26 @@ nsContentUtils::GetAncestorsAndOffsets(nsIDOMNode* aNode,
     return NS_ERROR_FAILURE;
   }
 
-  if (aAncestorNodes->Count() != 0) {
+  if (!aAncestorNodes->IsEmpty()) {
     NS_WARNING("aAncestorNodes is not empty");
     aAncestorNodes->Clear();
   }
 
-  if (aAncestorOffsets->Count() != 0) {
+  if (!aAncestorOffsets->IsEmpty()) {
     NS_WARNING("aAncestorOffsets is not empty");
     aAncestorOffsets->Clear();
   }
 
   // insert the node itself
   aAncestorNodes->AppendElement(content.get());
-  aAncestorOffsets->AppendElement(NS_INT32_TO_PTR(aOffset));
+  aAncestorOffsets->AppendElement(aOffset);
 
   // insert all the ancestors
   nsIContent* child = content;
   nsIContent* parent = child->GetParent();
   while (parent) {
     aAncestorNodes->AppendElement(parent);
-    aAncestorOffsets->AppendElement(NS_INT32_TO_PTR(parent->IndexOf(child)));
+    aAncestorOffsets->AppendElement(parent->IndexOf(child));
     child = parent;
     parent = parent->GetParent();
   }
diff --git a/content/base/src/nsDOMLists.h b/content/base/src/nsDOMLists.h
index 0be8f3ced121..fa2efde4228a 100644
--- a/content/base/src/nsDOMLists.h
+++ b/content/base/src/nsDOMLists.h
@@ -47,7 +47,6 @@
 
 #include "nsIDOMDOMStringList.h"
 #include "nsIDOMNameList.h"
-#include "nsVoidArray.h"
 #include "nsTArray.h"
 #include "nsString.h"
 
diff --git a/content/base/src/nsDocument.cpp b/content/base/src/nsDocument.cpp
index 341f74adefce..11dabf0bbbb3 100644
--- a/content/base/src/nsDocument.cpp
+++ b/content/base/src/nsDocument.cpp
@@ -2821,11 +2821,10 @@ nsDocument::SetDocumentCharacterSet(const nsACString& aCharSetID)
     }
 #endif
 
-    PRInt32 n = mCharSetObservers.Count();
+    PRInt32 n = mCharSetObservers.Length();
 
     for (PRInt32 i = 0; i < n; i++) {
-      nsIObserver* observer =
-        static_cast<nsIObserver *>(mCharSetObservers.ElementAt(i));
+      nsIObserver* observer = mCharSetObservers.ElementAt(i);
 
       observer->Observe(static_cast<nsIDocument *>(this), "charset",
                         NS_ConvertASCIItoUTF16(aCharSetID).get());
diff --git a/content/base/src/nsDocument.h b/content/base/src/nsDocument.h
index 1c8a999b7b1f..ed5dc90c4c32 100644
--- a/content/base/src/nsDocument.h
+++ b/content/base/src/nsDocument.h
@@ -49,6 +49,7 @@
 #include "nsWeakReference.h"
 #include "nsWeakPtr.h"
 #include "nsVoidArray.h"
+#include "nsTArray.h"
 #include "nsHashSets.h"
 #include "nsIDOMXMLDocument.h"
 #include "nsIDOM3Document.h"
@@ -1099,7 +1100,7 @@ protected:
   nsCString mReferrer;
   nsString mLastModified;
 
-  nsVoidArray mCharSetObservers;
+  nsTArray<nsIObserver*> mCharSetObservers;
 
   PLDHashTable *mSubDocuments;
 
diff --git a/content/base/src/nsDocumentEncoder.cpp b/content/base/src/nsDocumentEncoder.cpp
index 3e3579f99377..46773549ec49 100644
--- a/content/base/src/nsDocumentEncoder.cpp
+++ b/content/base/src/nsDocumentEncoder.cpp
@@ -76,6 +76,7 @@
 #include "nsContentUtils.h"
 #include "nsUnicharUtils.h"
 #include "nsReadableUtils.h"
+#include "nsTArray.h"
 
 nsresult NS_NewDomSelection(nsISelection **aDomSelection);
 
@@ -109,9 +110,9 @@ protected:
                                nsIDOMNode* aNode, 
                                nsAString& aString,
                                PRInt32 aDepth);
-  nsresult SerializeRangeContextStart(const nsVoidArray& aAncestorArray,
+  nsresult SerializeRangeContextStart(const nsTArray<nsIDOMNode*>& aAncestorArray,
                                       nsAString& aString);
-  nsresult SerializeRangeContextEnd(const nsVoidArray& aAncestorArray,
+  nsresult SerializeRangeContextEnd(const nsTArray<nsIDOMNode*>& aAncestorArray,
                                     nsAString& aString);
 
   nsresult FlushText(nsAString& aString, PRBool aForce);
@@ -139,11 +140,11 @@ protected:
   PRUint32          mEndDepth;
   PRInt32           mStartRootIndex;
   PRInt32           mEndRootIndex;
-  nsAutoVoidArray   mCommonAncestors;
-  nsAutoVoidArray   mStartNodes;
-  nsAutoVoidArray   mStartOffsets;
-  nsAutoVoidArray   mEndNodes;
-  nsAutoVoidArray   mEndOffsets;
+  nsAutoTArray<nsIDOMNode*, 8> mCommonAncestors;
+  nsAutoTArray<nsIContent*, 8> mStartNodes;
+  nsAutoTArray<PRInt32, 8>     mStartOffsets;
+  nsAutoTArray<nsIContent*, 8> mEndNodes;
+  nsAutoTArray<PRInt32, 8>     mEndOffsets;
   PRPackedBool      mHaltRangeHint;  
   PRPackedBool      mIsCopying;  // Set to PR_TRUE only while copying
   PRPackedBool      mNodeIsContainer;
@@ -542,18 +543,18 @@ static PRInt32 IndexOf(nsIDOMNode* aParent, nsIDOMNode* aChild)
   return parent->IndexOf(child);
 }
 
-static inline PRInt32 GetIndex(nsVoidArray& aIndexArray)
+static inline PRInt32 GetIndex(nsTArray<PRInt32>& aIndexArray)
 {
-  PRInt32 count = aIndexArray.Count();
+  PRInt32 count = aIndexArray.Length();
 
   if (count) {
-    return (PRInt32)aIndexArray.ElementAt(count - 1);
+    return aIndexArray.ElementAt(count - 1);
   }
 
   return 0;
 }
 
-static nsresult GetNextNode(nsIDOMNode* aNode, nsVoidArray& aIndexArray,
+static nsresult GetNextNode(nsIDOMNode* aNode, nsTArray<PRInt32>& aIndexArray,
                             nsIDOMNode*& aNextNode,
                             nsRangeIterationDirection& aDirection)
 {
@@ -567,7 +568,7 @@ static nsresult GetNextNode(nsIDOMNode* aNode, nsVoidArray& aIndexArray,
     ChildAt(aNode, 0, aNextNode);
     NS_ENSURE_TRUE(aNextNode, NS_ERROR_FAILURE);
 
-    aIndexArray.AppendElement((void *)0);
+    aIndexArray.AppendElement(0);
 
     aDirection = kDirectionIn;
   } else if (aDirection == kDirectionIn) {
@@ -582,15 +583,15 @@ static nsresult GetNextNode(nsIDOMNode* aNode, nsVoidArray& aIndexArray,
     aNode->GetParentNode(getter_AddRefs(parent));
     NS_ENSURE_TRUE(parent, NS_ERROR_FAILURE);
 
-    PRInt32 count = aIndexArray.Count();
+    PRInt32 count = aIndexArray.Length();
 
     if (count) {
-      PRInt32 indx = (PRInt32)aIndexArray.ElementAt(count - 1);
+      PRInt32 indx = aIndexArray.ElementAt(count - 1);
 
       ChildAt(parent, indx + 1, aNextNode);
 
       if (aNextNode)
-        aIndexArray.ReplaceElementAt((void *)(indx + 1), count - 1);
+        aIndexArray.ElementAt(count - 1) = indx + 1;
       else
         aIndexArray.RemoveElementAt(count - 1);
     } else {
@@ -600,7 +601,7 @@ static nsresult GetNextNode(nsIDOMNode* aNode, nsVoidArray& aIndexArray,
         ChildAt(parent, indx + 1, aNextNode);
 
         if (aNextNode)
-          aIndexArray.AppendElement((void *)(indx + 1));
+          aIndexArray.AppendElement(indx + 1);
       }
     }
 
@@ -670,12 +671,12 @@ nsDocumentEncoder::SerializeRangeNodes(nsIDOMRange* aRange,
   // get start and end nodes for this recursion level
   nsCOMPtr<nsIContent> startNode, endNode;
   PRInt32 start = mStartRootIndex - aDepth;
-  if (start >= 0 && start <= mStartNodes.Count())
-    startNode = static_cast<nsIContent *>(mStartNodes[start]);
+  if (start >= 0 && start <= mStartNodes.Length())
+    startNode = mStartNodes[start];
 
   PRInt32 end = mEndRootIndex - aDepth;
-  if (end >= 0 && end <= mEndNodes.Count())
-    endNode = static_cast<nsIContent *>(mEndNodes[end]);
+  if (end >= 0 && end <= mEndNodes.Length())
+    endNode = mEndNodes[end];
 
   if ((startNode != content) && (endNode != content))
   {
@@ -728,9 +729,9 @@ nsDocumentEncoder::SerializeRangeNodes(nsIDOMRange* aRange,
       nsCOMPtr<nsIDOMNode> childAsNode;
       PRInt32 startOffset = 0, endOffset = -1;
       if (startNode == content && mStartRootIndex >= aDepth)
-        startOffset = NS_PTR_TO_INT32(mStartOffsets[mStartRootIndex - aDepth]);
+        startOffset = mStartOffsets[mStartRootIndex - aDepth];
       if (endNode == content && mEndRootIndex >= aDepth)
-        endOffset = NS_PTR_TO_INT32(mEndOffsets[mEndRootIndex - aDepth]) ;
+        endOffset = mEndOffsets[mEndRootIndex - aDepth];
       // generated content will cause offset values of -1 to be returned.  
       PRInt32 j;
       PRUint32 childCount = content->GetChildCount();
@@ -777,14 +778,14 @@ nsDocumentEncoder::SerializeRangeNodes(nsIDOMRange* aRange,
 }
 
 nsresult
-nsDocumentEncoder::SerializeRangeContextStart(const nsVoidArray& aAncestorArray,
+nsDocumentEncoder::SerializeRangeContextStart(const nsTArray<nsIDOMNode*>& aAncestorArray,
                                               nsAString& aString)
 {
-  PRInt32 i = aAncestorArray.Count();
+  PRInt32 i = aAncestorArray.Length();
   nsresult rv = NS_OK;
 
   while (i > 0) {
-    nsIDOMNode *node = (nsIDOMNode *)aAncestorArray.ElementAt(--i);
+    nsIDOMNode *node = aAncestorArray.ElementAt(--i);
 
     if (!node)
       break;
@@ -801,15 +802,15 @@ nsDocumentEncoder::SerializeRangeContextStart(const nsVoidArray& aAncestorArray,
 }
 
 nsresult
-nsDocumentEncoder::SerializeRangeContextEnd(const nsVoidArray& aAncestorArray,
+nsDocumentEncoder::SerializeRangeContextEnd(const nsTArray<nsIDOMNode*>& aAncestorArray,
                                             nsAString& aString)
 {
   PRInt32 i = 0;
-  PRInt32 count = aAncestorArray.Count();
+  PRInt32 count = aAncestorArray.Length();
   nsresult rv = NS_OK;
 
   while (i < count) {
-    nsIDOMNode *node = (nsIDOMNode *)aAncestorArray.ElementAt(i++);
+    nsIDOMNode *node = aAncestorArray.ElementAt(i++);
 
     if (!node)
       break;
@@ -1256,11 +1257,11 @@ nsHTMLCopyEncoder::EncodeToStringWithContext(nsAString& aContextString,
   // where all the cells are in the same table.
 
   // leaf of ancestors might be text node.  If so discard it.
-  PRInt32 count = mCommonAncestors.Count();
+  PRInt32 count = mCommonAncestors.Length();
   PRInt32 i;
   nsCOMPtr<nsIDOMNode> node;
   if (count > 0)
-    node = static_cast<nsIDOMNode *>(mCommonAncestors.ElementAt(0));
+    node = mCommonAncestors.ElementAt(0);
 
   if (node && IsTextNode(node)) 
   {
@@ -1275,13 +1276,13 @@ nsHTMLCopyEncoder::EncodeToStringWithContext(nsAString& aContextString,
   i = count;
   while (i > 0)
   {
-    node = static_cast<nsIDOMNode *>(mCommonAncestors.ElementAt(--i));
+    node = mCommonAncestors.ElementAt(--i);
     SerializeNodeStart(node, 0, -1, aContextString);
   }
   //i = 0; guaranteed by above
   while (i < count)
   {
-    node = static_cast<nsIDOMNode *>(mCommonAncestors.ElementAt(i++));
+    node = mCommonAncestors.ElementAt(i++);
     SerializeNodeEnd(node, aContextString);
   }
 
diff --git a/content/base/src/nsGenericDOMDataNode.h b/content/base/src/nsGenericDOMDataNode.h
index 543eaaae14bb..291783b349d7 100644
--- a/content/base/src/nsGenericDOMDataNode.h
+++ b/content/base/src/nsGenericDOMDataNode.h
@@ -47,7 +47,6 @@
 #include "nsIDOMEventTarget.h"
 #include "nsIDOM3Text.h"
 #include "nsTextFragment.h"
-#include "nsVoidArray.h"
 #include "nsDOMError.h"
 #include "nsIEventListenerManager.h"
 #include "nsGenericElement.h"
diff --git a/content/base/src/nsGenericElement.h b/content/base/src/nsGenericElement.h
index 0d9ec89807a7..c6ecd2aa5fd2 100644
--- a/content/base/src/nsGenericElement.h
+++ b/content/base/src/nsGenericElement.h
@@ -76,7 +76,6 @@ class nsIDOMNamedNodeMap;
 class nsDOMCSSDeclaration;
 class nsIDOMCSSStyleDeclaration;
 class nsIURI;
-class nsVoidArray;
 class nsINodeInfo;
 class nsIControllers;
 class nsIDOMNSFeatureFactory;
diff --git a/content/base/src/nsHTMLContentSerializer.cpp b/content/base/src/nsHTMLContentSerializer.cpp
index d57e7af751f9..d6e816442a2c 100644
--- a/content/base/src/nsHTMLContentSerializer.cpp
+++ b/content/base/src/nsHTMLContentSerializer.cpp
@@ -101,12 +101,10 @@ nsHTMLContentSerializer::nsHTMLContentSerializer()
 
 nsHTMLContentSerializer::~nsHTMLContentSerializer()
 {
-  NS_ASSERTION(mOLStateStack.Count() == 0, "Expected OL State stack to be empty");
-  if (mOLStateStack.Count() > 0){
-    for (PRInt32 i = 0; i < mOLStateStack.Count(); i++){
-      olState* state = (olState*)mOLStateStack[i];
-      delete state;
-      mOLStateStack.RemoveElementAt(i);
+  NS_ASSERTION(mOLStateStack.IsEmpty(), "Expected OL State stack to be empty");
+  if (!mOLStateStack.IsEmpty()){
+    for (PRUint32 i = 0; i < mOLStateStack.Length(); i++){
+      delete mOLStateStack[i];
     }
   }
 }
@@ -788,12 +786,12 @@ nsHTMLContentSerializer::AppendElementEnd(nsIDOMElement *aElement,
   }
 
   if (mIsCopying && (name == nsGkAtoms::ol)){
-    NS_ASSERTION((mOLStateStack.Count() > 0), "Cannot have an empty OL Stack");
+    NS_ASSERTION(!mOLStateStack.IsEmpty(), "Cannot have an empty OL Stack");
     /* Though at this point we must always have an state to be deleted as all 
     the OL opening tags are supposed to push an olState object to the stack*/
-    if (mOLStateStack.Count() > 0) {
-      olState* state = (olState*)mOLStateStack.ElementAt(mOLStateStack.Count() -1);
-      mOLStateStack.RemoveElementAt(mOLStateStack.Count() -1);
+    if (!mOLStateStack.IsEmpty()) {
+      olState* state = mOLStateStack.ElementAt(mOLStateStack.Length() -1);
+      mOLStateStack.RemoveElementAt(mOLStateStack.Length() -1);
       delete state;
     }
   }
@@ -1243,12 +1241,12 @@ nsHTMLContentSerializer::SerializeLIValueAttribute(nsIDOMElement* aElement,
   PRInt32 offset = 0;
   olState defaultOLState(0, PR_FALSE);
   olState* state = nsnull;
-  if (mOLStateStack.Count() > 0) 
-    state = (olState*)mOLStateStack.ElementAt(mOLStateStack.Count()-1);
-  /* Though we should never reach to a "state" as null or mOLStateStack.Count() == 0 
+  if (!mOLStateStack.IsEmpty())
+    state = mOLStateStack.ElementAt(mOLStateStack.Length()-1);
+  /* Though we should never reach to a "state" as null or mOLStateStack.IsEmpty()
   at this point as all LI are supposed to be inside some OL and OL tag should have 
   pushed a state to the olStateStack.*/
-  if (!state || mOLStateStack.Count() == 0)
+  if (!state || mOLStateStack.IsEmpty())
     state = &defaultOLState;
   PRInt32 startVal = state->startVal;
   state->isFirstListItem = PR_FALSE;
@@ -1315,8 +1313,8 @@ nsHTMLContentSerializer::IsFirstChildOfOL(nsIDOMElement* aElement){
   if (parentName.LowerCaseEqualsLiteral("ol")) {
     olState defaultOLState(0, PR_FALSE);
     olState* state = nsnull;
-    if (mOLStateStack.Count() > 0) 
-      state = (olState*)mOLStateStack.ElementAt(mOLStateStack.Count()-1);
+    if (!mOLStateStack.IsEmpty())
+      state = mOLStateStack.ElementAt(mOLStateStack.Length()-1);
     /* Though we should never reach to a "state" as null at this point as 
     all LI are supposed to be inside some OL and OL tag should have pushed
     a state to the mOLStateStack.*/
diff --git a/content/base/src/nsHTMLContentSerializer.h b/content/base/src/nsHTMLContentSerializer.h
index 790a58ec39e1..eaa0966cd453 100644
--- a/content/base/src/nsHTMLContentSerializer.h
+++ b/content/base/src/nsHTMLContentSerializer.h
@@ -48,6 +48,7 @@
 #include "nsXMLContentSerializer.h"
 #include "nsIEntityConverter.h"
 #include "nsString.h"
+#include "nsTArray.h"
 
 class nsIContent;
 class nsIAtom;
@@ -168,7 +169,8 @@ class nsHTMLContentSerializer : public nsXMLContentSerializer {
     PRBool isFirstListItem;
   };
 
-  nsAutoVoidArray   mOLStateStack;// Stack to store one olState struct per <OL>.
+  // Stack to store one olState struct per <OL>.
+  nsAutoTArray<olState*, 8> mOLStateStack;
 };
 
 nsresult
diff --git a/content/base/src/nsPlainTextSerializer.cpp b/content/base/src/nsPlainTextSerializer.cpp
index bd57b0567b9c..88bdf4f36f46 100644
--- a/content/base/src/nsPlainTextSerializer.cpp
+++ b/content/base/src/nsPlainTextSerializer.cpp
@@ -235,21 +235,21 @@ nsPlainTextSerializer::Init(PRUint32 aFlags, PRUint32 aWrapColumn,
 }
 
 PRBool
-nsPlainTextSerializer::GetLastBool(const nsVoidArray& aStack)
+nsPlainTextSerializer::GetLastBool(const nsTArray<PRPackedBool>& aStack)
 {
-  PRUint32 size = aStack.Count();
+  PRUint32 size = aStack.Length();
   if (size == 0) {
     return PR_FALSE;
   }
-  return (aStack.ElementAt(size-1) != reinterpret_cast<void*>(PR_FALSE));
+  return aStack.ElementAt(size-1);
 }
 
 void
-nsPlainTextSerializer::SetLastBool(nsVoidArray& aStack, PRBool aValue)
+nsPlainTextSerializer::SetLastBool(nsTArray<PRPackedBool>& aStack, PRBool aValue)
 {
-  PRUint32 size = aStack.Count();
+  PRUint32 size = aStack.Length();
   if (size > 0) {
-    aStack.ReplaceElementAt(reinterpret_cast<void*>(aValue), size-1);
+    aStack.ElementAt(size-1) = aValue;
   }
   else {
     NS_ERROR("There is no \"Last\" value");
@@ -257,18 +257,18 @@ nsPlainTextSerializer::SetLastBool(nsVoidArray& aStack, PRBool aValue)
 }
 
 void
-nsPlainTextSerializer::PushBool(nsVoidArray& aStack, PRBool aValue)
+nsPlainTextSerializer::PushBool(nsTArray<PRPackedBool>& aStack, PRBool aValue)
 {
-    aStack.AppendElement(reinterpret_cast<void*>(aValue));
+    aStack.AppendElement(PRPackedBool(aValue));
 }
 
 PRBool
-nsPlainTextSerializer::PopBool(nsVoidArray& aStack)
+nsPlainTextSerializer::PopBool(nsTArray<PRPackedBool>& aStack)
 {
   PRBool returnValue = PR_FALSE;
-  PRUint32 size = aStack.Count();
+  PRUint32 size = aStack.Length();
   if (size > 0) {
-    returnValue = (aStack.ElementAt(size-1) != reinterpret_cast<void*>(PR_FALSE));
+    returnValue = aStack.ElementAt(size-1);
     aStack.RemoveElementAt(size-1);
   }
   return returnValue;
@@ -681,7 +681,7 @@ nsPlainTextSerializer::DoOpenContainer(const nsIParserNode* aNode, PRInt32 aTag)
       AddToLine(NS_LITERAL_STRING("\t").get(), 1);
       mInWhitespace = PR_TRUE;
     }
-    else if (mHasWrittenCellsForRow.Count() == 0) {
+    else if (mHasWrittenCellsForRow.IsEmpty()) {
       // We don't always see a <tr> (nor a <table>) before the <td> if we're
       // copying part of a table
       PushBool(mHasWrittenCellsForRow, PR_TRUE); // will never be popped
diff --git a/content/base/src/nsPlainTextSerializer.h b/content/base/src/nsPlainTextSerializer.h
index d484cf603627..d296c7333094 100644
--- a/content/base/src/nsPlainTextSerializer.h
+++ b/content/base/src/nsPlainTextSerializer.h
@@ -54,7 +54,7 @@
 #include "nsIAtom.h"
 #include "nsIHTMLToTextSink.h"
 #include "nsIDocumentEncoder.h"
-#include "nsVoidArray.h"
+#include "nsTArray.h"
 
 
 class nsPlainTextSerializer : public nsIContentSerializer,
@@ -164,10 +164,10 @@ protected:
   }
 
   // Stack handling functions
-  PRBool GetLastBool(const nsVoidArray& aStack);
-  void SetLastBool(nsVoidArray& aStack, PRBool aValue);
-  void PushBool(nsVoidArray& aStack, PRBool aValue);
-  PRBool PopBool(nsVoidArray& aStack);
+  PRBool GetLastBool(const nsTArray<PRPackedBool>& aStack);
+  void SetLastBool(nsTArray<PRPackedBool>& aStack, PRBool aValue);
+  void PushBool(nsTArray<PRPackedBool>& aStack, PRBool aValue);
+  PRBool PopBool(nsTArray<PRPackedBool>& aStack);
   
 protected:
   nsString         mCurrentLine;
@@ -241,11 +241,11 @@ protected:
   nsCOMPtr<nsIContent> mContent;
 
   // For handling table rows
-  nsAutoVoidArray mHasWrittenCellsForRow; // really an array of bools
+  nsAutoTArray<PRPackedBool, 8> mHasWrittenCellsForRow;
   
   // Values gotten in OpenContainer that is (also) needed in CloseContainer
-  nsAutoVoidArray     mCurrentNodeIsConverted; // really an array of bools
-  nsAutoVoidArray     mIsInCiteBlockquote; // really an array of bools
+  nsAutoTArray<PRPackedBool, 8> mCurrentNodeIsConverted;
+  nsAutoTArray<PRPackedBool, 8> mIsInCiteBlockquote;
 
   // The output data
   nsAString*            mOutputString;
diff --git a/content/base/src/nsRange.h b/content/base/src/nsRange.h
index 5b62a51e2610..cf7b9c498892 100644
--- a/content/base/src/nsRange.h
+++ b/content/base/src/nsRange.h
@@ -53,8 +53,6 @@
 #include "prmon.h"
 #include "nsStubMutationObserver.h"
 
-class nsVoidArray;
-
 // -------------------------------------------------------------------------------
 
 class nsRangeUtils : public nsIRangeUtils
diff --git a/content/base/src/nsScriptEventManager.h b/content/base/src/nsScriptEventManager.h
index 3f26f278c4b7..844727b3ce0d 100644
--- a/content/base/src/nsScriptEventManager.h
+++ b/content/base/src/nsScriptEventManager.h
@@ -44,7 +44,6 @@
 
 #include "nsCOMPtr.h"
 #include "nsAString.h"
-#include "nsVoidArray.h"
 
 #include "nsIScriptEventManager.h"
 #include "nsIDOMNodeList.h"
diff --git a/content/base/src/nsStyleLinkElement.cpp b/content/base/src/nsStyleLinkElement.cpp
index 8f2a7d8f6135..d85a09ca4e8e 100644
--- a/content/base/src/nsStyleLinkElement.cpp
+++ b/content/base/src/nsStyleLinkElement.cpp
@@ -57,7 +57,6 @@
 #include "nsISimpleUnicharStreamFactory.h"
 #include "nsNetUtil.h"
 #include "nsUnicharUtils.h"
-#include "nsVoidArray.h"
 #include "nsCRT.h"
 #include "nsXPCOMCIDInternal.h"
 #include "nsUnicharInputStream.h"
diff --git a/content/base/src/nsTreeWalker.cpp b/content/base/src/nsTreeWalker.cpp
index d412f1112288..b757d48f5d33 100644
--- a/content/base/src/nsTreeWalker.cpp
+++ b/content/base/src/nsTreeWalker.cpp
@@ -558,9 +558,8 @@ PRInt32 nsTreeWalker::IndexOf(nsINode* aParent,
                               nsINode* aChild,
                               PRInt32 aIndexPos)
 {
-    if (aIndexPos >= 0 && aIndexPos < mPossibleIndexes.Count()) {
-        PRInt32 possibleIndex =
-            NS_PTR_TO_INT32(mPossibleIndexes.FastElementAt(aIndexPos));
+    if (aIndexPos >= 0 && aIndexPos < PRInt32(mPossibleIndexes.Length())) {
+        PRInt32 possibleIndex = mPossibleIndexes.ElementAt(aIndexPos);
         if (aChild == aParent->GetChildAt(possibleIndex)) {
             return possibleIndex;
         }
diff --git a/content/base/src/nsTreeWalker.h b/content/base/src/nsTreeWalker.h
index acf5562c02a4..fce5172bd3e3 100644
--- a/content/base/src/nsTreeWalker.h
+++ b/content/base/src/nsTreeWalker.h
@@ -47,7 +47,7 @@
 #include "nsIDOMTreeWalker.h"
 #include "nsTraversal.h"
 #include "nsCOMPtr.h"
-#include "nsVoidArray.h"
+#include "nsTArray.h"
 #include "nsCycleCollectionParticipant.h"
 
 class nsINode;
@@ -74,9 +74,8 @@ private:
     /*
      * Array with all child indexes up the tree. This should only be
      * considered a hint and the value could be wrong.
-     * The array contains casted PRInt32's
      */
-    nsAutoVoidArray mPossibleIndexes;
+    nsAutoTArray<PRInt32, 8> mPossibleIndexes;
     
     /*
      * Position of mCurrentNode in mPossibleIndexes
@@ -168,9 +167,10 @@ private:
      */
     void SetChildIndex(PRInt32 aIndexPos, PRInt32 aChildIndex)
     {
-        if (aIndexPos != -1)
-            mPossibleIndexes.ReplaceElementAt(NS_INT32_TO_PTR(aChildIndex),
-                                              aIndexPos);
+        if (aIndexPos > 0) {
+            mPossibleIndexes.EnsureLengthAtLeast(aIndexPos+1);
+            mPossibleIndexes.ElementAt(aIndexPos) = aChildIndex;
+        }
     }
 };
 
diff --git a/content/base/src/nsXMLContentSerializer.cpp b/content/base/src/nsXMLContentSerializer.cpp
index 6f3fa5d07064..4f4536dd4ac6 100644
--- a/content/base/src/nsXMLContentSerializer.cpp
+++ b/content/base/src/nsXMLContentSerializer.cpp
@@ -64,11 +64,11 @@
 #include "nsContentUtils.h"
 #include "nsAttrName.h"
 
-typedef struct {
+struct NameSpaceDecl {
   nsString mPrefix;
   nsString mURI;
   nsIDOMElement* mOwner;
-} NameSpaceDecl;
+};
 
 nsresult NS_NewXMLContentSerializer(nsIContentSerializer** aSerializer)
 {
@@ -346,7 +346,7 @@ nsXMLContentSerializer::PushNameSpaceDecl(const nsAString& aPrefix,
   // we pop the stack
   decl->mOwner = aOwner;
 
-  mNameSpaceStack.AppendElement((void*)decl);
+  mNameSpaceStack.AppendElement(decl);
   return NS_OK;
 }
 
@@ -355,9 +355,9 @@ nsXMLContentSerializer::PopNameSpaceDeclsFor(nsIDOMElement* aOwner)
 {
   PRInt32 index, count;
 
-  count = mNameSpaceStack.Count();
+  count = mNameSpaceStack.Length();
   for (index = count - 1; index >= 0; index--) {
-    NameSpaceDecl* decl = (NameSpaceDecl*)mNameSpaceStack.ElementAt(index);
+    NameSpaceDecl* decl = mNameSpaceStack.ElementAt(index);
     if (decl->mOwner != aOwner) {
       break;
     }
@@ -411,10 +411,10 @@ nsXMLContentSerializer::ConfirmPrefix(nsAString& aPrefix,
   // later (so in a more outer scope) see it bound to aURI we can't reuse it.
   PRBool haveSeenOurPrefix = PR_FALSE;
 
-  PRInt32 count = mNameSpaceStack.Count();
+  PRInt32 count = mNameSpaceStack.Length();
   PRInt32 index = count - 1;
   while (index >= 0) {
-    NameSpaceDecl* decl = (NameSpaceDecl*)mNameSpaceStack.ElementAt(index);
+    NameSpaceDecl* decl = mNameSpaceStack.ElementAt(index);
     // Check if we've found a prefix match
     if (aPrefix.Equals(decl->mPrefix)) {
 
@@ -464,8 +464,7 @@ nsXMLContentSerializer::ConfirmPrefix(nsAString& aPrefix,
       PRBool prefixOK = PR_TRUE;
       PRInt32 index2;
       for (index2 = count-1; index2 > index && prefixOK; --index2) {
-        NameSpaceDecl* decl2 =
-          (NameSpaceDecl*)mNameSpaceStack.ElementAt(index2);
+        NameSpaceDecl* decl2 = mNameSpaceStack.ElementAt(index2);
         prefixOK = (decl2->mPrefix != decl->mPrefix);
       }
       
diff --git a/content/base/src/nsXMLContentSerializer.h b/content/base/src/nsXMLContentSerializer.h
index 57f4cf005f73..a2ca27210935 100644
--- a/content/base/src/nsXMLContentSerializer.h
+++ b/content/base/src/nsXMLContentSerializer.h
@@ -47,10 +47,12 @@
 #include "nsIContentSerializer.h"
 #include "nsISupportsUtils.h"
 #include "nsCOMPtr.h"
-#include "nsVoidArray.h"
+#include "nsTArray.h"
+#include "nsString.h"
 
 class nsIDOMNode;
 class nsIAtom;
+struct NameSpaceDecl;
 
 class nsXMLContentSerializer : public nsIContentSerializer {
  public:
@@ -156,7 +158,7 @@ class nsXMLContentSerializer : public nsIContentSerializer {
   void MaybeFlagNewline(nsIDOMNode* aNode);
 
   PRInt32 mPrefixIndex;
-  nsVoidArray mNameSpaceStack;
+  nsTArray<NameSpaceDecl*> mNameSpaceStack;
 
   // nsIDocumentEncoder flags
   PRUint32  mFlags;
diff --git a/content/base/src/nsXMLNameSpaceMap.cpp b/content/base/src/nsXMLNameSpaceMap.cpp
index 025709e135d9..ad12e767a3fb 100644
--- a/content/base/src/nsXMLNameSpaceMap.cpp
+++ b/content/base/src/nsXMLNameSpaceMap.cpp
@@ -82,12 +82,11 @@ nsXMLNameSpaceMap::nsXMLNameSpaceMap()
 nsresult
 nsXMLNameSpaceMap::AddPrefix(nsIAtom *aPrefix, PRInt32 aNameSpaceID)
 {
-  PRInt32 count = mNameSpaces.Count();
+  PRUint32 count = mNameSpaces.Length();
   nsNameSpaceEntry *foundEntry = nsnull;
 
-  for (PRInt32 i = 0; i < count; ++i) {
-    nsNameSpaceEntry *entry = static_cast<nsNameSpaceEntry*>
-                                         (mNameSpaces.FastElementAt(i));
+  for (PRUint32 i = 0; i < count; ++i) {
+    nsNameSpaceEntry *entry = mNameSpaces.ElementAt(i);
 
     NS_ASSERTION(entry, "null entry in namespace map!");
 
@@ -101,7 +100,7 @@ nsXMLNameSpaceMap::AddPrefix(nsIAtom *aPrefix, PRInt32 aNameSpaceID)
     foundEntry = new nsNameSpaceEntry(aPrefix);
     NS_ENSURE_TRUE(foundEntry, NS_ERROR_OUT_OF_MEMORY);
 
-    if (!mNameSpaces.AppendElement(foundEntry)) {
+    if (mNameSpaces.AppendElement(foundEntry) == nsnull) {
       delete foundEntry;
       return NS_ERROR_OUT_OF_MEMORY;
     }
@@ -126,11 +125,10 @@ nsXMLNameSpaceMap::AddPrefix(nsIAtom *aPrefix, nsString &aURI)
 void
 nsXMLNameSpaceMap::RemovePrefix(nsIAtom *aPrefix)
 {
-  PRInt32 count = mNameSpaces.Count();
+  PRUint32 count = mNameSpaces.Length();
 
-  for (PRInt32 i = 0; i < count; ++i) {
-    nsNameSpaceEntry *entry = static_cast<nsNameSpaceEntry*>
-                                         (mNameSpaces.FastElementAt(i));
+  for (PRUint32 i = 0; i < count; ++i) {
+    nsNameSpaceEntry *entry = mNameSpaces.ElementAt(i);
 
     NS_ASSERTION(entry, "null entry in namespace map!");
 
@@ -144,11 +142,10 @@ nsXMLNameSpaceMap::RemovePrefix(nsIAtom *aPrefix)
 PRInt32
 nsXMLNameSpaceMap::FindNameSpaceID(nsIAtom *aPrefix) const
 {
-  PRInt32 count = mNameSpaces.Count();
+  PRUint32 count = mNameSpaces.Length();
 
-  for (PRInt32 i = 0; i < count; ++i) {
-    nsNameSpaceEntry *entry = static_cast<nsNameSpaceEntry*>
-                                         (mNameSpaces.FastElementAt(i));
+  for (PRUint32 i = 0; i < count; ++i) {
+    nsNameSpaceEntry *entry = mNameSpaces.ElementAt(i);
 
     NS_ASSERTION(entry, "null entry in namespace map!");
 
@@ -166,11 +163,10 @@ nsXMLNameSpaceMap::FindNameSpaceID(nsIAtom *aPrefix) const
 nsIAtom*
 nsXMLNameSpaceMap::FindPrefix(PRInt32 aNameSpaceID) const
 {
-  PRInt32 count = mNameSpaces.Count();
+  PRUint32 count = mNameSpaces.Length();
 
-  for (PRInt32 i = 0; i < count; ++i) {
-    nsNameSpaceEntry *entry = static_cast<nsNameSpaceEntry*>
-                                         (mNameSpaces.FastElementAt(i));
+  for (PRUint32 i = 0; i < count; ++i) {
+    nsNameSpaceEntry *entry = mNameSpaces.ElementAt(i);
 
     NS_ASSERTION(entry, "null entry in namespace map!");
 
@@ -182,14 +178,11 @@ nsXMLNameSpaceMap::FindPrefix(PRInt32 aNameSpaceID) const
   return nsnull;
 }
 
-static PRBool DeleteEntry(void *aElement, void *aData)
-{
-  delete static_cast<nsNameSpaceEntry*>(aElement);
-  return PR_TRUE;
-}
-
 void
 nsXMLNameSpaceMap::Clear()
 {
-  mNameSpaces.EnumerateForwards(DeleteEntry, nsnull);
+  for (PRUint32 i = 0, len = mNameSpaces.Length(); i < len; ++i) {
+    delete mNameSpaces[i];
+  }
+  mNameSpaces.Clear();
 }
diff --git a/content/html/document/src/nsHTMLContentSink.cpp b/content/html/document/src/nsHTMLContentSink.cpp
index a7a7a0947242..ac2779d19b5f 100644
--- a/content/html/document/src/nsHTMLContentSink.cpp
+++ b/content/html/document/src/nsHTMLContentSink.cpp
@@ -94,7 +94,6 @@
 #include "nsINameSpaceManager.h"
 #include "nsIDOMHTMLMapElement.h"
 #include "nsICookieService.h"
-#include "nsVoidArray.h"
 #include "nsTArray.h"
 #include "nsIScriptSecurityManager.h"
 #include "nsIPrincipal.h"
@@ -247,7 +246,7 @@ protected:
 
   nsRefPtr<nsGenericHTMLElement> mCurrentForm;
 
-  nsAutoVoidArray mContextStack;
+  nsAutoTArray<SinkContext*, 8> mContextStack;
   SinkContext* mCurrentContext;
   SinkContext* mHeadContext;
   PRInt32 mNumOpenIFRAMES;
@@ -1550,7 +1549,7 @@ HTMLContentSink::~HTMLContentSink()
     mNotificationTimer->Cancel();
   }
 
-  PRInt32 numContexts = mContextStack.Count();
+  PRInt32 numContexts = mContextStack.Length();
 
   if (mCurrentContext == mHeadContext && numContexts > 0) {
     // Pop off the second html context if it's not done earlier
@@ -1559,7 +1558,7 @@ HTMLContentSink::~HTMLContentSink()
 
   PRInt32 i;
   for (i = 0; i < numContexts; i++) {
-    SinkContext* sc = (SinkContext*)mContextStack.ElementAt(i);
+    SinkContext* sc = mContextStack.ElementAt(i);
     if (sc) {
       sc->End();
       if (sc == mCurrentContext) {
@@ -1923,8 +1922,8 @@ HTMLContentSink::EndContext(PRInt32 aPosition)
   MOZ_TIMER_START(mWatch);
   NS_PRECONDITION(mCurrentContext && aPosition > -1, "non-existing context");
 
-  PRInt32 n = mContextStack.Count() - 1;
-  SinkContext* sc = (SinkContext*) mContextStack.ElementAt(n);
+  PRUint32 n = mContextStack.Length() - 1;
+  SinkContext* sc = mContextStack.ElementAt(n);
 
   const SinkContext::Node &bottom = mCurrentContext->mStack[0];
   
@@ -1985,10 +1984,10 @@ HTMLContentSink::CloseHTML()
 
   if (mHeadContext) {
     if (mCurrentContext == mHeadContext) {
-      PRInt32 numContexts = mContextStack.Count();
+      PRUint32 numContexts = mContextStack.Length();
 
       // Pop off the second html context if it's not done earlier
-      mCurrentContext = (SinkContext*)mContextStack.ElementAt(--numContexts);
+      mCurrentContext = mContextStack.ElementAt(--numContexts);
       mContextStack.RemoveElementAt(numContexts);
     }
 
@@ -2832,11 +2831,12 @@ HTMLContentSink::CloseHeadContext()
     mCurrentContext->FlushTextAndRelease();
   }
 
-  NS_ASSERTION(mContextStack.Count() > 0, "Stack should not be empty");
-  
-  PRInt32 n = mContextStack.Count() - 1;
-  mCurrentContext = (SinkContext*) mContextStack.ElementAt(n);
-  mContextStack.RemoveElementAt(n);
+  if (!mContextStack.IsEmpty())
+  {
+    PRUint32 n = mContextStack.Length() - 1;
+    mCurrentContext = mContextStack.ElementAt(n);
+    mContextStack.RemoveElementAt(n);
+  }
 }
 
 void
@@ -3070,9 +3070,9 @@ HTMLContentSink::IsMonolithicContainer(nsHTMLTag aTag)
 void
 HTMLContentSink::UpdateChildCounts()
 {
-  PRInt32 numContexts = mContextStack.Count();
-  for (PRInt32 i = 0; i < numContexts; i++) {
-    SinkContext* sc = (SinkContext*)mContextStack.ElementAt(i);
+  PRUint32 numContexts = mContextStack.Length();
+  for (PRUint32 i = 0; i < numContexts; i++) {
+    SinkContext* sc = mContextStack.ElementAt(i);
 
     sc->UpdateChildCounts();
   }
diff --git a/content/html/document/src/nsHTMLDocument.cpp b/content/html/document/src/nsHTMLDocument.cpp
index a66d247970e2..b04336f846a3 100644
--- a/content/html/document/src/nsHTMLDocument.cpp
+++ b/content/html/document/src/nsHTMLDocument.cpp
@@ -2083,9 +2083,7 @@ nsHTMLDocument::Close()
   if (mParser && mWriteState == eDocumentOpened) {
     mPendingScripts.RemoveElement(GenerateParserKey());
 
-    mWriteState = mPendingScripts.Count() == 0
-                  ? eDocumentClosed
-                  : ePendingClose;
+    mWriteState = mPendingScripts.IsEmpty() ? eDocumentClosed : ePendingClose;
 
     ++mWriteLevel;
     rv = mParser->Parse(EmptyString(), mParser->GetRootContextKey(),
@@ -2150,7 +2148,7 @@ nsHTMLDocument::WriteCommon(const nsAString& aText,
   void *key = GenerateParserKey();
   if (mWriteState == eDocumentClosed ||
       (mWriteState == ePendingClose &&
-       mPendingScripts.IndexOf(key) == kNotFound)) {
+       !mPendingScripts.Contains(key))) {
     mWriteState = eDocumentClosed;
     mParser->Terminate();
     NS_ASSERTION(!mParser, "mParser should have been null'd out");
@@ -2370,7 +2368,7 @@ nsHTMLDocument::ScriptExecuted(nsIScriptElement *aScript)
   }
 
   mPendingScripts.RemoveElement(aScript);
-  if (mPendingScripts.Count() == 0 && mWriteState == ePendingClose) {
+  if (mPendingScripts.IsEmpty() && mWriteState == ePendingClose) {
     // The last pending script just finished, terminate our parser now.
     mWriteState = eDocumentClosed;
   }
diff --git a/content/html/document/src/nsHTMLDocument.h b/content/html/document/src/nsHTMLDocument.h
index c931290fe852..42a99dec96fd 100644
--- a/content/html/document/src/nsHTMLDocument.h
+++ b/content/html/document/src/nsHTMLDocument.h
@@ -47,6 +47,7 @@
 #include "nsIDOMHTMLCollection.h"
 #include "nsIScriptElement.h"
 #include "jsapi.h"
+#include "nsTArray.h"
 
 #include "pldhash.h"
 #include "nsIHttpChannel.h"
@@ -342,7 +343,7 @@ protected:
   // finishes processing that script.
   PRUint32 mWriteLevel;
 
-  nsSmallVoidArray mPendingScripts;
+  nsAutoTArray<nsIScriptElement*, 1> mPendingScripts;
 
   // Load flags of the document's channel
   PRUint32 mLoadFlags;
diff --git a/content/html/document/src/nsHTMLFragmentContentSink.cpp b/content/html/document/src/nsHTMLFragmentContentSink.cpp
index 9380a12fbe51..485909f21286 100644
--- a/content/html/document/src/nsHTMLFragmentContentSink.cpp
+++ b/content/html/document/src/nsHTMLFragmentContentSink.cpp
@@ -49,7 +49,7 @@
 #include "nsIDOMComment.h"
 #include "nsIDOMHTMLFormElement.h"
 #include "nsIDOMDocumentFragment.h"
-#include "nsVoidArray.h"
+#include "nsTArray.h"
 #include "nsINameSpaceManager.h"
 #include "nsIDocument.h"
 #include "nsINodeInfo.h"
@@ -150,7 +150,7 @@ public:
   nsCOMPtr<nsIContent> mRoot;
   nsCOMPtr<nsIParser> mParser;
 
-  nsVoidArray* mContentStack;
+  nsTArray<nsIContent*>* mContentStack;
 
   PRUnichar* mText;
   PRInt32 mTextLength;
@@ -210,9 +210,9 @@ nsHTMLFragmentContentSink::~nsHTMLFragmentContentSink()
 
   if (nsnull != mContentStack) {
     // there shouldn't be anything here except in an error condition
-    PRInt32 indx = mContentStack->Count();
+    PRInt32 indx = mContentStack->Length();
     while (0 < indx--) {
-      nsIContent* content = (nsIContent*)mContentStack->ElementAt(indx);
+      nsIContent* content = mContentStack->ElementAt(indx);
       NS_RELEASE(content);
     }
     delete mContentStack;
@@ -680,9 +680,9 @@ nsIContent*
 nsHTMLFragmentContentSink::GetCurrentContent()
 {
   if (nsnull != mContentStack) {
-    PRInt32 indx = mContentStack->Count() - 1;
+    PRInt32 indx = mContentStack->Length() - 1;
     if (indx >= 0)
-      return (nsIContent *)mContentStack->ElementAt(indx);
+      return mContentStack->ElementAt(indx);
   }
   return nsnull;
 }
@@ -691,11 +691,11 @@ PRInt32
 nsHTMLFragmentContentSink::PushContent(nsIContent *aContent)
 {
   if (nsnull == mContentStack) {
-    mContentStack = new nsVoidArray();
+    mContentStack = new nsTArray<nsIContent*>();
   }
 
-  mContentStack->AppendElement((void *)aContent);
-  return mContentStack->Count();
+  mContentStack->AppendElement(aContent);
+  return mContentStack->Length();
 }
 
 nsIContent*
@@ -703,9 +703,9 @@ nsHTMLFragmentContentSink::PopContent()
 {
   nsIContent* content = nsnull;
   if (nsnull != mContentStack) {
-    PRInt32 indx = mContentStack->Count() - 1;
+    PRInt32 indx = mContentStack->Length() - 1;
     if (indx >= 0) {
-      content = (nsIContent *)mContentStack->ElementAt(indx);
+      content = mContentStack->ElementAt(indx);
       mContentStack->RemoveElementAt(indx);
     }
   }
diff --git a/content/svg/content/src/nsSVGDataParser.h b/content/svg/content/src/nsSVGDataParser.h
index 2661827afb55..7140556b4549 100644
--- a/content/svg/content/src/nsSVGDataParser.h
+++ b/content/svg/content/src/nsSVGDataParser.h
@@ -39,7 +39,6 @@
 #define __NS_SVGDATAPARSER_H__
 
 #include "nsCOMPtr.h"
-#include "nsVoidArray.h"
 
 //----------------------------------------------------------------------
 // helper macros
diff --git a/content/svg/content/src/nsSVGLengthList.cpp b/content/svg/content/src/nsSVGLengthList.cpp
index d94bfd94bb4c..3c142153f35c 100644
--- a/content/svg/content/src/nsSVGLengthList.cpp
+++ b/content/svg/content/src/nsSVGLengthList.cpp
@@ -40,7 +40,7 @@
 #include "nsSVGLength.h"
 #include "nsSVGValue.h"
 #include "nsWeakReference.h"
-#include "nsVoidArray.h"
+#include "nsTArray.h"
 #include "nsDOMError.h"
 #include "nsReadableUtils.h"
 #include "nsSVGSVGElement.h"
@@ -93,7 +93,7 @@ protected:
   
   void ReleaseLengths();
   
-  nsAutoVoidArray mLengths;
+  nsAutoTArray<nsISVGLength*, 1> mLengths;
   nsWeakPtr mContext;  // needs to be weak to avoid reference loop
   PRUint8 mCtxType;
 };
@@ -168,11 +168,11 @@ nsSVGLengthList::GetValueString(nsAString& aValue)
 {
   aValue.Truncate();
 
-  PRInt32 count = mLengths.Count();
+  PRUint32 count = mLengths.Length();
 
-  if (count<=0) return NS_OK;
+  if (count == 0) return NS_OK;
 
-  PRInt32 i = 0;
+  PRUint32 i = 0;
   
   while (1) {
     nsISVGLength* length = ElementAt(i);
@@ -197,7 +197,7 @@ nsSVGLengthList::GetValueString(nsAString& aValue)
 /* readonly attribute unsigned long numberOfItems; */
 NS_IMETHODIMP nsSVGLengthList::GetNumberOfItems(PRUint32 *aNumberOfItems)
 {
-  *aNumberOfItems = mLengths.Count();
+  *aNumberOfItems = mLengths.Length();
   return NS_OK;
 }
 
@@ -225,7 +225,7 @@ NS_IMETHODIMP nsSVGLengthList::Initialize(nsIDOMSVGLength *newItem,
 /* nsIDOMSVGLength getItem (in unsigned long index); */
 NS_IMETHODIMP nsSVGLengthList::GetItem(PRUint32 index, nsIDOMSVGLength **_retval)
 {
-  if (index >= static_cast<PRUint32>(mLengths.Count())) {
+  if (index >= mLengths.Length()) {
     *_retval = nsnull;
     return NS_ERROR_DOM_INDEX_SIZE_ERR;
   }
@@ -266,7 +266,7 @@ nsSVGLengthList::ReplaceItem(nsIDOMSVGLength *newItem,
 /* nsIDOMSVGLengthList removeItem (in unsigned long index); */
 NS_IMETHODIMP nsSVGLengthList::RemoveItem(PRUint32 index, nsIDOMSVGLength **_retval)
 {
-  if (index >= static_cast<PRUint32>(mLengths.Count())) {
+  if (index >= mLengths.Length()) {
     *_retval = nsnull;
     return NS_ERROR_DOM_INDEX_SIZE_ERR;
   }
@@ -321,8 +321,8 @@ void
 nsSVGLengthList::ReleaseLengths()
 {
   WillModify();
-  PRInt32 count = mLengths.Count();
-  for (PRInt32 i = 0; i < count; ++i) {
+  PRUint32 count = mLengths.Length();
+  for (PRUint32 i = 0; i < count; ++i) {
     nsISVGLength* length = ElementAt(i);
     length->SetContext(nsnull, 0);
     NS_REMOVE_SVGVALUE_OBSERVER(length);
@@ -335,7 +335,7 @@ nsSVGLengthList::ReleaseLengths()
 nsISVGLength*
 nsSVGLengthList::ElementAt(PRInt32 index)
 {
-  return (nsISVGLength*)mLengths.ElementAt(index);
+  return mLengths.ElementAt(index);
 }
 
 void
@@ -350,7 +350,7 @@ nsSVGLengthList::AppendElement(nsISVGLength* aElement)
   //  aElement->SetListOwner(this);
   
   aElement->SetContext(mContext, mCtxType);
-  mLengths.AppendElement((void*)aElement);
+  mLengths.AppendElement(aElement);
   NS_ADD_SVGVALUE_OBSERVER(aElement);
   DidModify();
 }
@@ -380,7 +380,7 @@ nsSVGLengthList::InsertElementAt(nsISVGLength* aElement, PRInt32 index)
   
   aElement->SetContext(mContext, mCtxType);
   
-  mLengths.InsertElementAt((void*)aElement, index);
+  mLengths.InsertElementAt(index, aElement);
   NS_ADD_SVGVALUE_OBSERVER(aElement);
   DidModify();
 }
diff --git a/content/svg/content/src/nsSVGNumberList.cpp b/content/svg/content/src/nsSVGNumberList.cpp
index af9494a705f2..b58c9f30982c 100644
--- a/content/svg/content/src/nsSVGNumberList.cpp
+++ b/content/svg/content/src/nsSVGNumberList.cpp
@@ -40,7 +40,6 @@
 #include "nsSVGNumber.h"
 #include "nsSVGValue.h"
 #include "nsWeakReference.h"
-#include "nsVoidArray.h"
 #include "nsDOMError.h"
 #include "nsReadableUtils.h"
 #include "nsCRT.h"
@@ -91,7 +90,7 @@ protected:
   
   void ReleaseNumbers();
   
-  nsAutoVoidArray mNumbers;
+  nsAutoTArray<nsIDOMSVGNumber*, 8> mNumbers;
 };
 
 
@@ -165,11 +164,11 @@ nsSVGNumberList::GetValueString(nsAString& aValue)
 {
   aValue.Truncate();
 
-  PRInt32 count = mNumbers.Count();
+  PRUint32 count = mNumbers.Length();
 
-  if (count<=0) return NS_OK;
+  if (count == 0) return NS_OK;
 
-  PRInt32 i = 0;
+  PRUint32 i = 0;
   
   while (1) {
     nsIDOMSVGNumber* number = ElementAt(i);
@@ -194,7 +193,7 @@ nsSVGNumberList::GetValueString(nsAString& aValue)
 /* readonly attribute unsigned long numberOfItems; */
 NS_IMETHODIMP nsSVGNumberList::GetNumberOfItems(PRUint32 *aNumberOfItems)
 {
-  *aNumberOfItems = mNumbers.Count();
+  *aNumberOfItems = mNumbers.Length();
   return NS_OK;
 }
 
@@ -222,7 +221,7 @@ NS_IMETHODIMP nsSVGNumberList::Initialize(nsIDOMSVGNumber *newItem,
 /* nsIDOMSVGNumber getItem (in unsigned long index); */
 NS_IMETHODIMP nsSVGNumberList::GetItem(PRUint32 index, nsIDOMSVGNumber **_retval)
 {
-  if (index >= static_cast<PRUint32>(mNumbers.Count())) {
+  if (index >= mNumbers.Length()) {
     *_retval = nsnull;
     return NS_ERROR_DOM_INDEX_SIZE_ERR;
   }
@@ -244,10 +243,9 @@ nsSVGNumberList::InsertItemBefore(nsIDOMSVGNumber *newItem,
 
   nsSVGValueAutoNotifier autonotifier(this);
 
-  PRInt32 idx = index;
-  PRInt32 count = mNumbers.Count();
+  PRUint32 count = mNumbers.Length();
 
-  if (!InsertElementAt(newItem, (idx < count)? idx: count)) {
+  if (!InsertElementAt(newItem, (index < count)? index: count)) {
     *_retval = nsnull;
     return NS_ERROR_OUT_OF_MEMORY;
   }
@@ -277,7 +275,7 @@ nsSVGNumberList::ReplaceItem(nsIDOMSVGNumber *newItem,
 /* nsIDOMSVGNumberList removeItem (in unsigned long index); */
 NS_IMETHODIMP nsSVGNumberList::RemoveItem(PRUint32 index, nsIDOMSVGNumber **_retval)
 {
-  if (index >= static_cast<PRUint32>(mNumbers.Count())) {
+  if (index >= mNumbers.Length()) {
     *_retval = nsnull;
     return NS_ERROR_DOM_INDEX_SIZE_ERR;
   }
@@ -328,8 +326,8 @@ void
 nsSVGNumberList::ReleaseNumbers()
 {
   WillModify();
-  PRInt32 count = mNumbers.Count();
-  for (PRInt32 i = 0; i < count; ++i) {
+  PRUint32 count = mNumbers.Length();
+  for (PRUint32 i = 0; i < count; ++i) {
     nsIDOMSVGNumber* number = ElementAt(i);
     NS_REMOVE_SVGVALUE_OBSERVER(number);
     NS_RELEASE(number);
@@ -341,7 +339,7 @@ nsSVGNumberList::ReleaseNumbers()
 nsIDOMSVGNumber*
 nsSVGNumberList::ElementAt(PRInt32 index)
 {
-  return (nsIDOMSVGNumber*)mNumbers.ElementAt(index);
+  return mNumbers.ElementAt(index);
 }
 
 void
@@ -355,7 +353,7 @@ nsSVGNumberList::AppendElement(nsIDOMSVGNumber* aElement)
   // list':
   //  aElement->SetListOwner(this);
   
-  mNumbers.AppendElement((void*)aElement);
+  mNumbers.AppendElement(aElement);
   NS_ADD_SVGVALUE_OBSERVER(aElement);
   DidModify();
 }
@@ -384,7 +382,7 @@ nsSVGNumberList::InsertElementAt(nsIDOMSVGNumber* aElement, PRInt32 index)
   // list':
   //  aElement->SetListOwner(this);
   
-  if (!NS_FAILED(rv = mNumbers.InsertElementAt((void*)aElement, index)))
+  if (mNumbers.InsertElementAt(index, aElement))
     NS_ADD_SVGVALUE_OBSERVER(aElement);
   DidModify();
   return rv;
diff --git a/content/svg/content/src/nsSVGPathDataParser.h b/content/svg/content/src/nsSVGPathDataParser.h
index 558a01c3e556..140453cf2fbf 100644
--- a/content/svg/content/src/nsSVGPathDataParser.h
+++ b/content/svg/content/src/nsSVGPathDataParser.h
@@ -41,7 +41,6 @@
 
 #include "nsSVGDataParser.h"
 #include "nsCOMPtr.h"
-#include "nsVoidArray.h"
 #include "nsCOMArray.h"
 #include "nsIDOMSVGPathSeg.h"
 #include "nsTArray.h"
diff --git a/content/svg/content/src/nsSVGPathSegList.cpp b/content/svg/content/src/nsSVGPathSegList.cpp
index ac16e5068047..0e3c1c5dc1aa 100644
--- a/content/svg/content/src/nsSVGPathSegList.cpp
+++ b/content/svg/content/src/nsSVGPathSegList.cpp
@@ -40,7 +40,6 @@
 #include "nsSVGPathSeg.h"
 #include "nsSVGValue.h"
 #include "nsWeakReference.h"
-#include "nsVoidArray.h"
 #include "nsCOMArray.h"
 #include "nsDOMError.h"
 #include "nsSVGPathDataParser.h"
diff --git a/content/svg/content/src/nsSVGPointList.cpp b/content/svg/content/src/nsSVGPointList.cpp
index 5be972f95a09..ce9641e50fa1 100644
--- a/content/svg/content/src/nsSVGPointList.cpp
+++ b/content/svg/content/src/nsSVGPointList.cpp
@@ -82,8 +82,8 @@ void
 nsSVGPointList::ReleasePoints()
 {
   WillModify();
-  PRInt32 count = mPoints.Count();
-  for (PRInt32 i = 0; i < count; ++i) {
+  PRUint32 count = mPoints.Length();
+  for (PRUint32 i = 0; i < count; ++i) {
     nsIDOMSVGPoint* point = ElementAt(i);
     nsCOMPtr<nsISVGValue> val = do_QueryInterface(point);
     if (val)
@@ -97,7 +97,7 @@ nsSVGPointList::ReleasePoints()
 nsIDOMSVGPoint*
 nsSVGPointList::ElementAt(PRInt32 index)
 {
-  return (nsIDOMSVGPoint*)mPoints.ElementAt(index);
+  return mPoints.ElementAt(index);
 }
 
 void
@@ -105,7 +105,7 @@ nsSVGPointList::AppendElement(nsIDOMSVGPoint* aElement)
 {
   WillModify();
   NS_ADDREF(aElement);
-  mPoints.AppendElement((void*)aElement);
+  mPoints.AppendElement(aElement);
   nsCOMPtr<nsISVGValue> val = do_QueryInterface(aElement);
   if (val)
     val->AddObserver(this);
@@ -131,7 +131,7 @@ nsSVGPointList::InsertElementAt(nsIDOMSVGPoint* aElement, PRInt32 index)
 {
   WillModify();
   NS_ADDREF(aElement);
-  mPoints.InsertElementAt((void*)aElement, index);
+  mPoints.InsertElementAt(index, aElement);
   nsCOMPtr<nsISVGValue> val = do_QueryInterface(aElement);
   if (val)
     val->AddObserver(this);
@@ -219,11 +219,11 @@ nsSVGPointList::GetValueString(nsAString& aValue)
 {
   aValue.Truncate();
 
-  PRInt32 count = mPoints.Count();
+  PRUint32 count = mPoints.Length();
 
-  if (count<=0) return NS_OK;
+  if (count == 0) return NS_OK;
 
-  PRInt32 i = 0;
+  PRUint32 i = 0;
   PRUnichar buf[48];
   
   while (1) {
@@ -249,7 +249,7 @@ nsSVGPointList::GetValueString(nsAString& aValue)
 /* readonly attribute unsigned long numberOfItems; */
 NS_IMETHODIMP nsSVGPointList::GetNumberOfItems(PRUint32 *aNumberOfItems)
 {
-  *aNumberOfItems = mPoints.Count();
+  *aNumberOfItems = mPoints.Length();
   return NS_OK;
 }
 
@@ -277,7 +277,7 @@ NS_IMETHODIMP nsSVGPointList::Initialize(nsIDOMSVGPoint *newItem,
 /* nsIDOMSVGPoint getItem (in unsigned long index); */
 NS_IMETHODIMP nsSVGPointList::GetItem(PRUint32 index, nsIDOMSVGPoint **_retval)
 {
-  if (index >= static_cast<PRUint32>(mPoints.Count())) {
+  if (index >= mPoints.Length()) {
     *_retval = nsnull;
     return NS_ERROR_DOM_INDEX_SIZE_ERR;
   }
@@ -316,7 +316,7 @@ NS_IMETHODIMP nsSVGPointList::ReplaceItem(nsIDOMSVGPoint *newItem,
 /* nsIDOMSVGPoint removeItem (in unsigned long index); */
 NS_IMETHODIMP nsSVGPointList::RemoveItem(PRUint32 index, nsIDOMSVGPoint **_retval)
 {
-  if (index >= static_cast<PRUint32>(mPoints.Count())) {
+  if (index >= mPoints.Length()) {
     *_retval = nsnull;
     return NS_ERROR_DOM_INDEX_SIZE_ERR;
   }
diff --git a/content/svg/content/src/nsSVGPointList.h b/content/svg/content/src/nsSVGPointList.h
index fcb99f95453b..528ce126e02d 100644
--- a/content/svg/content/src/nsSVGPointList.h
+++ b/content/svg/content/src/nsSVGPointList.h
@@ -43,7 +43,7 @@
 #include "nsISVGValueObserver.h"
 #include "nsWeakReference.h"
 #include "nsIDOMSVGPointList.h"
-#include "nsVoidArray.h"
+#include "nsTArray.h"
 
 
 class nsSVGPointList : public nsSVGValue,
@@ -88,7 +88,7 @@ public:
 protected:
   void ReleasePoints();
   
-  nsAutoVoidArray mPoints;
+  nsAutoTArray<nsIDOMSVGPoint*, 8> mPoints;
 };
 
 
diff --git a/content/svg/content/src/nsSVGTransformList.cpp b/content/svg/content/src/nsSVGTransformList.cpp
index 0991484456d4..1d20170a2e28 100644
--- a/content/svg/content/src/nsSVGTransformList.cpp
+++ b/content/svg/content/src/nsSVGTransformList.cpp
@@ -80,8 +80,8 @@ nsSVGTransformList::~nsSVGTransformList()
 void
 nsSVGTransformList::ReleaseTransforms()
 {
-  PRInt32 count = mTransforms.Count();
-  for (PRInt32 i = 0; i < count; ++i) {
+  PRUint32 count = mTransforms.Length();
+  for (PRUint32 i = 0; i < count; ++i) {
     nsIDOMSVGTransform* transform = ElementAt(i);
     nsCOMPtr<nsISVGValue> val = do_QueryInterface(transform);
     val->RemoveObserver(this);
@@ -93,20 +93,20 @@ nsSVGTransformList::ReleaseTransforms()
 nsIDOMSVGTransform*
 nsSVGTransformList::ElementAt(PRInt32 index)
 {
-  return (nsIDOMSVGTransform*)mTransforms.ElementAt(index);
+  return mTransforms.ElementAt(index);
 }
 
 PRBool
 nsSVGTransformList::AppendElement(nsIDOMSVGTransform* aElement)
 {
-  PRBool rv = mTransforms.AppendElement((void*)aElement);
-  if (rv) {
+  if (mTransforms.AppendElement(aElement)) {
     NS_ADDREF(aElement);
     nsCOMPtr<nsISVGValue> val = do_QueryInterface(aElement);
     val->AddObserver(this);
+    return PR_TRUE;
   }
 
-  return rv;
+  return PR_FALSE;
 }
 
 already_AddRefed<nsIDOMSVGMatrix>
@@ -199,11 +199,11 @@ nsSVGTransformList::GetValueString(nsAString& aValue)
 {
   aValue.Truncate();
 
-  PRInt32 count = mTransforms.Count();
+  PRUint32 count = mTransforms.Length();
 
-  if (count<=0) return NS_OK;
+  if (count == 0) return NS_OK;
 
-  PRInt32 i = 0;
+  PRUint32 i = 0;
   
   while (1) {
     nsIDOMSVGTransform* transform = ElementAt(i);
@@ -228,7 +228,7 @@ nsSVGTransformList::GetValueString(nsAString& aValue)
 /* readonly attribute unsigned long numberOfItems; */
 NS_IMETHODIMP nsSVGTransformList::GetNumberOfItems(PRUint32 *aNumberOfItems)
 {
-  *aNumberOfItems = mTransforms.Count();
+  *aNumberOfItems = mTransforms.Length();
   return NS_OK;
 }
 
@@ -262,7 +262,7 @@ NS_IMETHODIMP nsSVGTransformList::Initialize(nsIDOMSVGTransform *newItem,
 /* nsIDOMSVGTransform getItem (in unsigned long index); */
 NS_IMETHODIMP nsSVGTransformList::GetItem(PRUint32 index, nsIDOMSVGTransform **_retval)
 {
-  if (index >= static_cast<PRUint32>(mTransforms.Count())) {
+  if (index >= mTransforms.Length()) {
     *_retval = nsnull;
     return NS_ERROR_DOM_INDEX_SIZE_ERR;
   }
@@ -281,9 +281,9 @@ NS_IMETHODIMP nsSVGTransformList::InsertItemBefore(nsIDOMSVGTransform *newItem,
 
   nsSVGValueAutoNotifier autonotifier(this);
 
-  PRUint32 count = mTransforms.Count();
+  PRUint32 count = mTransforms.Length();
 
-  if (!mTransforms.InsertElementAt((void*)newItem, (index < count)? index: count)) {
+  if (!mTransforms.InsertElementAt((index < count)? index: count, newItem)) {
     return NS_ERROR_OUT_OF_MEMORY;
   }
 
@@ -305,15 +305,12 @@ NS_IMETHODIMP nsSVGTransformList::ReplaceItem(nsIDOMSVGTransform *newItem,
 
   nsSVGValueAutoNotifier autonotifier(this);
 
-  if (index >= PRUint32(mTransforms.Count()))
+  if (index >= mTransforms.Length())
     return NS_ERROR_DOM_INDEX_SIZE_ERR;
 
   nsIDOMSVGTransform* oldItem = ElementAt(index);
 
-  if (!mTransforms.ReplaceElementAt((void*)newItem, index)) {
-    NS_NOTREACHED("removal of element failed");
-    return NS_ERROR_UNEXPECTED;
-  }
+  mTransforms.ElementAt(index) = newItem;
 
   nsCOMPtr<nsISVGValue> val = do_QueryInterface(oldItem);
   val->RemoveObserver(this);
@@ -332,18 +329,14 @@ NS_IMETHODIMP nsSVGTransformList::RemoveItem(PRUint32 index, nsIDOMSVGTransform
 {
   nsSVGValueAutoNotifier autonotifier(this);
 
-  if (index >= static_cast<PRUint32>(mTransforms.Count())) {
+  if (index >= mTransforms.Length()) {
     *_retval = nsnull;
     return NS_ERROR_DOM_INDEX_SIZE_ERR;
   }
 
   *_retval = ElementAt(index);
 
-  if (!mTransforms.RemoveElementAt(index)) {
-    NS_NOTREACHED("removal of element failed");
-    *_retval = nsnull;
-    return NS_ERROR_UNEXPECTED;
-  }
+  mTransforms.RemoveElementAt(index);
 
   nsCOMPtr<nsISVGValue> val = do_QueryInterface(*_retval);
   val->RemoveObserver(this);
@@ -392,7 +385,7 @@ NS_IMETHODIMP nsSVGTransformList::Consolidate(nsIDOMSVGTransform **_retval)
 
   *_retval = nsnull;
 
-  PRInt32 count = mTransforms.Count();
+  PRUint32 count = mTransforms.Length();
   if (count==0) return NS_OK;
   if (count==1) {
     *_retval = ElementAt(0);
diff --git a/content/svg/content/src/nsSVGTransformList.h b/content/svg/content/src/nsSVGTransformList.h
index 4362c07493b4..80bda1d2305c 100644
--- a/content/svg/content/src/nsSVGTransformList.h
+++ b/content/svg/content/src/nsSVGTransformList.h
@@ -43,7 +43,7 @@
 #include "nsISVGValueObserver.h"
 #include "nsWeakReference.h"
 #include "nsIDOMSVGTransformList.h"
-#include "nsVoidArray.h"
+#include "nsTArray.h"
 
 class nsSVGTransformList : public nsSVGValue,
                            public nsIDOMSVGTransformList,
@@ -87,7 +87,7 @@ protected:
   PRInt32 ParseParameterList(char *paramstr, float *vars, PRInt32 nvars);
   void ReleaseTransforms();
   
-  nsAutoVoidArray mTransforms;
+  nsAutoTArray<nsIDOMSVGTransform*, 8> mTransforms;
 };
 
 
diff --git a/content/svg/content/src/nsSVGValue.cpp b/content/svg/content/src/nsSVGValue.cpp
index ea235ea00bf1..419326f70db3 100644
--- a/content/svg/content/src/nsSVGValue.cpp
+++ b/content/svg/content/src/nsSVGValue.cpp
@@ -52,27 +52,26 @@ nsSVGValue::~nsSVGValue()
 void
 nsSVGValue::ReleaseObservers()
 {
-  PRInt32 count = mObservers.Count();
-  PRInt32 i;
+  PRUint32 count = mObservers.Length();
+  PRUint32 i;
   for (i = 0; i < count; ++i) {
-    nsIWeakReference* wr = static_cast<nsIWeakReference*>(mObservers.ElementAt(i));
+    nsIWeakReference* wr = mObservers.ElementAt(i);
     NS_RELEASE(wr);
   }
-  while (i)
-    mObservers.RemoveElementAt(--i);
+  mObservers.Clear();
 }
 
 void
 nsSVGValue::NotifyObservers(SVGObserverNotifyFunction f,
                             modificationType aModType)
 {
-  PRInt32 count = mObservers.Count();
+  PRInt32 count = mObservers.Length();
 
   // Since notification might cause the listeners to remove themselves
   // from the observer list (mod_die), walk backwards through the list
   // to catch everyone.
   for (PRInt32 i = count - 1; i >= 0; i--) {
-    nsIWeakReference* wr = static_cast<nsIWeakReference*>(mObservers.ElementAt(i));
+    nsIWeakReference* wr = mObservers.ElementAt(i);
     nsCOMPtr<nsISVGValueObserver> observer = do_QueryReferent(wr);
     if (observer)
        (static_cast<nsISVGValueObserver*>(observer)->*f)(this, aModType);
@@ -108,12 +107,12 @@ nsSVGValue::AddObserver(nsISVGValueObserver* observer)
   // stroke and fill.  Safe, as on a style change we remove both, as
   // the change notification isn't fine grained, and re-add as
   // appropriate.
-  if (mObservers.IndexOf((void*)wr) >= 0) {
+  if (mObservers.Contains(wr)) {
     NS_RELEASE(wr);
     return NS_OK;
   }
 
-  mObservers.AppendElement((void*)wr);
+  mObservers.AppendElement(wr);
   return NS_OK;
 }
 
@@ -122,9 +121,9 @@ nsSVGValue::RemoveObserver(nsISVGValueObserver* observer)
 {
   nsCOMPtr<nsIWeakReference> wr = do_GetWeakReference(observer);
   if (!wr) return NS_ERROR_FAILURE;
-  PRInt32 i = mObservers.IndexOf((void*)wr);
+  PRInt32 i = mObservers.IndexOf(wr);
   if (i<0) return NS_ERROR_FAILURE;
-  nsIWeakReference* wr2 = static_cast<nsIWeakReference*>(mObservers.ElementAt(i));
+  nsIWeakReference* wr2 = mObservers.ElementAt(i);
   NS_RELEASE(wr2);
   mObservers.RemoveElementAt(i);
   return NS_OK;
diff --git a/content/svg/content/src/nsSVGValue.h b/content/svg/content/src/nsSVGValue.h
index 292afe6fb651..1eab0073dec2 100644
--- a/content/svg/content/src/nsSVGValue.h
+++ b/content/svg/content/src/nsSVGValue.h
@@ -42,7 +42,7 @@
 #include "nscore.h"
 #include "nsISVGValue.h"
 #include "nsAutoPtr.h"
-#include "nsVoidArray.h"
+#include "nsTArray.h"
 #include "nsISVGValueObserver.h"
 
 class nsSVGValue : public nsISVGValue
@@ -80,7 +80,7 @@ protected:
 private:
   virtual void OnDidModify(){} // hook that will be called before observers are notified
   
-  nsSmallVoidArray mObservers;
+  nsAutoTArray<nsIWeakReference*, 1> mObservers;
   PRInt32 mModifyNestCount;
 };
 
diff --git a/content/xbl/src/nsXBLEventHandler.cpp b/content/xbl/src/nsXBLEventHandler.cpp
index 46df94f972d6..fb1428cd9bca 100644
--- a/content/xbl/src/nsXBLEventHandler.cpp
+++ b/content/xbl/src/nsXBLEventHandler.cpp
@@ -136,9 +136,8 @@ nsXBLKeyEventHandler::ExecuteMatchedHandlers(nsIDOMKeyEvent* aKeyEvent,
   nsCOMPtr<nsPIDOMEventTarget> piTarget = do_QueryInterface(target);
 
   PRBool executed = PR_FALSE;
-  for (PRUint32 i = 0; i < mProtoHandlers.Count(); ++i) {
-    nsXBLPrototypeHandler* handler = static_cast<nsXBLPrototypeHandler*>
-                                                (mProtoHandlers[i]);
+  for (PRUint32 i = 0; i < mProtoHandlers.Length(); ++i) {
+    nsXBLPrototypeHandler* handler = mProtoHandlers[i];
     PRBool hasAllowUntrustedAttr = handler->HasAllowUntrustedAttr();
     if ((trustedEvent ||
         (hasAllowUntrustedAttr && handler->AllowUntrustedEvents()) ||
@@ -154,7 +153,7 @@ nsXBLKeyEventHandler::ExecuteMatchedHandlers(nsIDOMKeyEvent* aKeyEvent,
 NS_IMETHODIMP
 nsXBLKeyEventHandler::HandleEvent(nsIDOMEvent* aEvent)
 {
-  PRUint32 count = mProtoHandlers.Count();
+  PRUint32 count = mProtoHandlers.Length();
   if (count == 0)
     return NS_ERROR_FAILURE;
 
diff --git a/content/xbl/src/nsXBLEventHandler.h b/content/xbl/src/nsXBLEventHandler.h
index 6c984dfb0e1d..9d8a0fea5dda 100644
--- a/content/xbl/src/nsXBLEventHandler.h
+++ b/content/xbl/src/nsXBLEventHandler.h
@@ -41,7 +41,7 @@
 
 #include "nsCOMPtr.h"
 #include "nsIDOMEventListener.h"
-#include "nsVoidArray.h"
+#include "nsTArray.h"
 
 class nsIAtom;
 class nsIContent;
@@ -125,7 +125,7 @@ private:
   PRBool ExecuteMatchedHandlers(nsIDOMKeyEvent* aEvent, PRUint32 aCharCode,
                                 PRBool aIgnoreShiftKey);
 
-  nsVoidArray mProtoHandlers;
+  nsTArray<nsXBLPrototypeHandler*> mProtoHandlers;
   nsCOMPtr<nsIAtom> mEventType;
   PRUint8 mPhase;
   PRUint8 mType;
diff --git a/content/xbl/src/nsXBLService.cpp b/content/xbl/src/nsXBLService.cpp
index 8baef5df837e..650de8894343 100644
--- a/content/xbl/src/nsXBLService.cpp
+++ b/content/xbl/src/nsXBLService.cpp
@@ -74,6 +74,7 @@
 #include "nsSyncLoadService.h"
 #include "nsIDOM3Node.h"
 #include "nsContentPolicyUtils.h"
+#include "nsTArray.h"
 
 #include "nsIPresShell.h"
 #include "nsIDocumentObserver.h"
@@ -332,7 +333,7 @@ private:
   nsXBLService* mXBLService; // [WEAK]
 
   nsCOMPtr<nsIStreamListener> mInner;
-  nsAutoVoidArray mBindingRequests;
+  nsAutoTArray<nsXBLBindingRequest*, 8> mBindingRequests;
   
   nsCOMPtr<nsIWeakReference> mBoundDocument;
   nsCOMPtr<nsIXMLContentSink> mSink; // Only set until OnStartRequest
@@ -355,8 +356,8 @@ nsXBLStreamListener::nsXBLStreamListener(nsXBLService* aXBLService,
 
 nsXBLStreamListener::~nsXBLStreamListener()
 {
-  for (PRInt32 i = 0; i < mBindingRequests.Count(); i++) {
-    nsXBLBindingRequest* req = (nsXBLBindingRequest*)mBindingRequests.ElementAt(i);
+  for (PRInt32 i = 0; i < mBindingRequests.Length(); i++) {
+    nsXBLBindingRequest* req = mBindingRequests.ElementAt(i);
     nsXBLBindingRequest::Destroy(mXBLService->mPool, req);
   }
 }
@@ -421,9 +422,9 @@ PRBool
 nsXBLStreamListener::HasRequest(nsIURI* aURI, nsIContent* aElt)
 {
   // XXX Could be more efficient.
-  PRUint32 count = mBindingRequests.Count();
+  PRUint32 count = mBindingRequests.Length();
   for (PRUint32 i = 0; i < count; i++) {
-    nsXBLBindingRequest* req = (nsXBLBindingRequest*)mBindingRequests.ElementAt(i);
+    nsXBLBindingRequest* req = mBindingRequests.ElementAt(i);
     PRBool eq;
     if (req->mBoundElement == aElt &&
         NS_SUCCEEDED(req->mBindingURI->Equals(aURI, &eq)) && eq)
@@ -438,7 +439,7 @@ nsXBLStreamListener::Load(nsIDOMEvent* aEvent)
 {
   nsresult rv = NS_OK;
   PRUint32 i;
-  PRUint32 count = mBindingRequests.Count();
+  PRUint32 count = mBindingRequests.Length();
 
   // Get the binding document; note that we don't hold onto it in this object
   // to avoid creating a cycle
@@ -460,7 +461,7 @@ nsXBLStreamListener::Load(nsIDOMEvent* aEvent)
     // We need to get the sink's notifications flushed and then make the binding
     // ready.
     if (count > 0) {
-      nsXBLBindingRequest* req = (nsXBLBindingRequest*)mBindingRequests.ElementAt(0);
+      nsXBLBindingRequest* req = mBindingRequests.ElementAt(0);
       nsIDocument* document = req->mBoundElement->GetCurrentDoc();
       if (document)
         document->FlushPendingNotifications(Flush_ContentAndNotify);
@@ -500,7 +501,7 @@ nsXBLStreamListener::Load(nsIDOMEvent* aEvent)
     // Notify all pending requests that their bindings are
     // ready and can be installed.
     for (i = 0; i < count; i++) {
-      nsXBLBindingRequest* req = (nsXBLBindingRequest*)mBindingRequests.ElementAt(i);
+      nsXBLBindingRequest* req = mBindingRequests.ElementAt(i);
       req->DocumentLoaded(bindingDocument);
     }
   }
diff --git a/content/xml/document/src/nsXMLContentSink.cpp b/content/xml/document/src/nsXMLContentSink.cpp
index 314ce70af2f4..686d15b300bc 100644
--- a/content/xml/document/src/nsXMLContentSink.cpp
+++ b/content/xml/document/src/nsXMLContentSink.cpp
@@ -58,7 +58,6 @@
 #include "nsIDOMCDATASection.h"
 #include "nsDOMDocumentType.h"
 #include "nsHTMLParts.h"
-#include "nsVoidArray.h"
 #include "nsCRT.h"
 #include "nsICSSLoader.h"
 #include "nsICSSStyleSheet.h"
diff --git a/content/xslt/src/base/txNamespaceMap.cpp b/content/xslt/src/base/txNamespaceMap.cpp
index 077cb64d6b9b..6e91d1ba84a0 100644
--- a/content/xslt/src/base/txNamespaceMap.cpp
+++ b/content/xslt/src/base/txNamespaceMap.cpp
@@ -79,7 +79,7 @@ txNamespaceMap::mapNamespace(nsIAtom* aPrefix, const nsAString& aNamespaceURI)
     // Check if the mapping already exists
     PRInt32 index = mPrefixes.IndexOf(prefix);
     if (index >= 0) {
-        mNamespaces.ReplaceElementAt(NS_INT32_TO_PTR(nsId), index);
+        mNamespaces.ElementAt(index) = nsId;
 
         return NS_OK;
     }
@@ -89,7 +89,7 @@ txNamespaceMap::mapNamespace(nsIAtom* aPrefix, const nsAString& aNamespaceURI)
         return NS_ERROR_OUT_OF_MEMORY;
     }
     
-    if (!mNamespaces.AppendElement(NS_INT32_TO_PTR(nsId))) {
+    if (mNamespaces.AppendElement(nsId) == nsnull) {
         mPrefixes.RemoveObjectAt(mPrefixes.Count() - 1);
 
         return NS_ERROR_OUT_OF_MEMORY;
@@ -109,7 +109,7 @@ txNamespaceMap::lookupNamespace(nsIAtom* aPrefix)
 
     PRInt32 index = mPrefixes.IndexOf(prefix);
     if (index >= 0) {
-        return NS_PTR_TO_INT32(mNamespaces.SafeElementAt(index));
+        return mNamespaces.SafeElementAt(index, kNameSpaceID_Unknown);
     }
 
     if (!prefix) {
diff --git a/content/xslt/src/base/txNamespaceMap.h b/content/xslt/src/base/txNamespaceMap.h
index 766d709daf4c..8db9707618c2 100644
--- a/content/xslt/src/base/txNamespaceMap.h
+++ b/content/xslt/src/base/txNamespaceMap.h
@@ -41,6 +41,7 @@
 
 #include "nsIAtom.h"
 #include "nsCOMArray.h"
+#include "nsTArray.h"
 
 class txNamespaceMap
 {
@@ -70,7 +71,7 @@ public:
 private:
     nsAutoRefCnt mRefCnt;
     nsCOMArray<nsIAtom> mPrefixes;
-    nsVoidArray mNamespaces;
+    nsTArray<PRInt32> mNamespaces;
 };
 
 #endif //TRANSFRMX_TXNAMESPACEMAP_H
diff --git a/content/xslt/src/base/txStack.h b/content/xslt/src/base/txStack.h
index 8993bd209778..8d22842d3c6f 100644
--- a/content/xslt/src/base/txStack.h
+++ b/content/xslt/src/base/txStack.h
@@ -39,9 +39,9 @@
 #ifndef txStack_h___
 #define txStack_h___
 
-#include "nsVoidArray.h"
+#include "nsTArray.h"
 
-class txStack : private nsVoidArray
+class txStack : private nsTArray<void*>
 {
 public:
     /**
@@ -53,7 +53,7 @@ public:
     inline void* peek()
     {
         NS_ASSERTION(!isEmpty(), "peeking at empty stack");
-        return ElementAt(Count() - 1);
+        return !isEmpty() ? ElementAt(Length() - 1) : nsnull;
     }
 
     /**
@@ -64,8 +64,7 @@ public:
      */
     inline nsresult push(void* aObject)
     {
-        return InsertElementAt(aObject, Count()) ? NS_OK :
-                                                   NS_ERROR_OUT_OF_MEMORY;
+        return AppendElement(aObject) ? NS_OK : NS_ERROR_OUT_OF_MEMORY;
     }
 
     /**
@@ -76,10 +75,14 @@ public:
      */
     inline void* pop()
     {
+        void* object = nsnull;
         NS_ASSERTION(!isEmpty(), "popping from empty stack");
-        const PRInt32 count = Count() - 1;
-        void* object = ElementAt(count);
-        RemoveElementsAt(count, 1);
+        if (!isEmpty())
+        {
+            const PRUint32 count = Length() - 1;
+            object = ElementAt(count);
+            RemoveElementAt(count);
+        }
         return object;
     }
 
@@ -90,7 +93,7 @@ public:
      */
     inline PRBool isEmpty()
     {
-        return (Count() <= 0);
+        return IsEmpty();
     }
 
     /**
@@ -100,7 +103,7 @@ public:
      */
     inline PRInt32 size()
     {
-        return Count();
+        return Length();
     }
 
 private:
@@ -128,7 +131,7 @@ public:
      */
     inline PRBool hasNext()
     {
-        return (mPosition < mStack->Count());
+        return (mPosition < mStack->Length());
     }
 
     /**
@@ -138,7 +141,7 @@ public:
      */
     inline void* next()
     {
-        if (mPosition == mStack->Count()) {
+        if (mPosition == mStack->Length()) {
             return nsnull;
         }
         return mStack->ElementAt(mPosition++);
@@ -146,7 +149,7 @@ public:
 
 private:
     txStack* mStack;
-    PRInt32 mPosition;
+    PRUint32 mPosition;
 };
 
 #endif /* txStack_h___ */
diff --git a/content/xslt/src/main/testXalan.cpp b/content/xslt/src/main/testXalan.cpp
index f1ca1e2fb770..7a4f17f41111 100644
--- a/content/xslt/src/main/testXalan.cpp
+++ b/content/xslt/src/main/testXalan.cpp
@@ -44,7 +44,6 @@
 #include "nsILocalFile.h"
 #include "nsISimpleEnumerator.h"
 #include "nsString.h"
-#include "nsVoidArray.h"
 #include "prenv.h"
 #include "prsystem.h"
 #include "nsDirectoryServiceUtils.h"
diff --git a/content/xslt/src/xml/txDOM.h b/content/xslt/src/xml/txDOM.h
index d8c37a2d82df..a6275726898e 100644
--- a/content/xslt/src/xml/txDOM.h
+++ b/content/xslt/src/xml/txDOM.h
@@ -57,7 +57,6 @@
 #include "nsIAtom.h"
 #include "nsDoubleHashtable.h"
 #include "nsString.h"
-#include "nsVoidArray.h"
 #include "txCore.h"
 #include "nsAutoPtr.h"
 
diff --git a/content/xslt/src/xml/txNodeDefinition.cpp b/content/xslt/src/xml/txNodeDefinition.cpp
index 03acbeee291b..6e448d9734ff 100644
--- a/content/xslt/src/xml/txNodeDefinition.cpp
+++ b/content/xslt/src/xml/txNodeDefinition.cpp
@@ -46,7 +46,6 @@
 //
 
 #include "txDOM.h"
-#include "nsVoidArray.h"
 #include "nsTArray.h"
 #include "txURIUtils.h"
 #include "txAtoms.h"
diff --git a/content/xslt/src/xpath/txMozillaXPathTreeWalker.cpp b/content/xslt/src/xpath/txMozillaXPathTreeWalker.cpp
index 1449e7d9b88a..c2730126fdc6 100644
--- a/content/xslt/src/xpath/txMozillaXPathTreeWalker.cpp
+++ b/content/xslt/src/xpath/txMozillaXPathTreeWalker.cpp
@@ -54,6 +54,7 @@
 #include "txLog.h"
 #include "nsUnicharUtils.h"
 #include "nsAttrName.h"
+#include "nsTArray.h"
 
 const PRUint32 kUnknownIndex = PRUint32(-1);
 
@@ -209,9 +210,9 @@ txXPathTreeWalker::moveToFirstChild()
     }
 
     NS_ASSERTION(!mPosition.isDocument() ||
-                 (mCurrentIndex == kUnknownIndex && !mDescendants.Count()),
+                 (mCurrentIndex == kUnknownIndex && mDescendants.IsEmpty()),
                  "we shouldn't have any position info at the document");
-    NS_ASSERTION(mCurrentIndex != kUnknownIndex || !mDescendants.Count(),
+    NS_ASSERTION(mCurrentIndex != kUnknownIndex || mDescendants.IsEmpty(),
                  "Index should be known if parents index are");
 
     nsIContent* child = mPosition.mNode->GetChildAt(0);
@@ -238,9 +239,9 @@ txXPathTreeWalker::moveToLastChild()
     }
 
     NS_ASSERTION(!mPosition.isDocument() ||
-                 (mCurrentIndex == kUnknownIndex && !mDescendants.Count()),
+                 (mCurrentIndex == kUnknownIndex && mDescendants.IsEmpty()),
                  "we shouldn't have any position info at the document");
-    NS_ASSERTION(mCurrentIndex != kUnknownIndex || !mDescendants.Count(),
+    NS_ASSERTION(mCurrentIndex != kUnknownIndex || mDescendants.IsEmpty(),
                  "Index should be known if parents index are");
 
     PRUint32 total = mPosition.mNode->GetChildCount();
@@ -296,7 +297,7 @@ txXPathTreeWalker::moveToParent()
         return PR_FALSE;
     }
 
-    PRInt32 count = mDescendants.Count();
+    PRUint32 count = mDescendants.Length();
     if (count) {
         mCurrentIndex = mDescendants.ValueAt(--count);
         mDescendants.RemoveValueAt(count);
@@ -691,7 +692,7 @@ txXPathNodeUtils::comparePosition(const txXPathNode& aNode,
     // same tree.
 
     // Get parents up the tree.
-    nsAutoVoidArray parents, otherParents;
+    nsAutoTArray<nsINode*, 8> parents, otherParents;
     nsINode* node = aNode.mNode;
     nsINode* otherNode = aOtherNode.mNode;
     nsINode* parent, *otherParent;
@@ -727,17 +728,16 @@ txXPathNodeUtils::comparePosition(const txXPathNode& aNode,
     }
 
     // Walk back down along the parent-chains until we find where they split.
-    PRInt32 total = parents.Count() - 1;
-    PRInt32 otherTotal = otherParents.Count() - 1;
+    PRInt32 total = parents.Length() - 1;
+    PRInt32 otherTotal = otherParents.Length() - 1;
     NS_ASSERTION(total != otherTotal, "Can't have same number of parents");
 
     PRInt32 lastIndex = PR_MIN(total, otherTotal);
     PRInt32 i;
     parent = nsnull;
     for (i = 0; i <= lastIndex; ++i) {
-        node = static_cast<nsINode*>(parents.ElementAt(total - i));
-        otherNode = static_cast<nsINode*>
-                               (otherParents.ElementAt(otherTotal - i));
+        node = parents.ElementAt(total - i);
+        otherNode = otherParents.ElementAt(otherTotal - i);
         if (node != otherNode) {
             if (!parent) {
                 // The two nodes are in different orphan subtrees.
diff --git a/content/xslt/src/xpath/txNodeSet.h b/content/xslt/src/xpath/txNodeSet.h
index 797e81b98d8c..4f0dfb30321f 100644
--- a/content/xslt/src/xpath/txNodeSet.h
+++ b/content/xslt/src/xpath/txNodeSet.h
@@ -44,7 +44,6 @@
 #define txNodeSet_h__
 
 #include "txExprResult.h"
-#include "nsVoidArray.h"
 #include "txError.h"
 #include "txXPathNode.h"
 
diff --git a/content/xslt/src/xpath/txXPathTreeWalker.h b/content/xslt/src/xpath/txXPathTreeWalker.h
index 7fd951e105af..a11e09fa0486 100644
--- a/content/xslt/src/xpath/txXPathTreeWalker.h
+++ b/content/xslt/src/xpath/txXPathTreeWalker.h
@@ -46,22 +46,25 @@ class nsIAtom;
 
 #ifndef TX_EXE
 #include "nsINodeInfo.h"
-#include "nsVoidArray.h"
+#include "nsTArray.h"
 
-class txUint32Array : public nsVoidArray
+class txUint32Array : public nsTArray<PRUint32>
 {
 public:
     PRBool AppendValue(PRUint32 aValue)
     {
-        return InsertElementAt(NS_INT32_TO_PTR(aValue), Count());
+        return AppendElement(aValue) != nsnull;
     }
     PRBool RemoveValueAt(PRUint32 aIndex)
     {
-        return RemoveElementsAt(aIndex, 1);
+        if (aIndex < Length()) {
+            RemoveElementAt(aIndex);
+        }
+        return PR_TRUE;
     }
-    PRInt32 ValueAt(PRUint32 aIndex) const
+    PRUint32 ValueAt(PRUint32 aIndex) const
     {
-        return NS_PTR_TO_INT32(ElementAt(aIndex));
+        return (aIndex < Length()) ? ElementAt(aIndex) : 0;
     }
 };
 
diff --git a/content/xslt/src/xslt/txBufferingHandler.cpp b/content/xslt/src/xslt/txBufferingHandler.cpp
index 402eabef4668..7e690c3f24ae 100644
--- a/content/xslt/src/xslt/txBufferingHandler.cpp
+++ b/content/xslt/src/xslt/txBufferingHandler.cpp
@@ -343,22 +343,17 @@ txBufferingHandler::startElement(nsIAtom* aPrefix,
     return mBuffer->addTransaction(transaction);
 }
 
-static PRBool
-deleteTransaction(void* aElement, void *aData)
-{
-    delete static_cast<txOutputTransaction*>(aElement);
-    return PR_TRUE;
-}
-
 txResultBuffer::~txResultBuffer()
 {
-    mTransactions.EnumerateForwards(deleteTransaction, nsnull);
+    for (PRUint32 i, len = mTransactions.Length(); i < len; ++i) {
+        delete mTransactions[i];
+    }
 }
 
 nsresult
 txResultBuffer::addTransaction(txOutputTransaction* aTransaction)
 {
-    if (!mTransactions.AppendElement(aTransaction)) {
+    if (mTransactions.AppendElement(aTransaction) == nsnull) {
         return NS_ERROR_OUT_OF_MEMORY;
     }
     return NS_OK;
@@ -372,12 +367,11 @@ struct Holder
 };
 
 static PRBool
-flushTransaction(void* aElement, void *aData)
+flushTransaction(txOutputTransaction* aElement, Holder* aData)
 {
-    Holder* holder = static_cast<Holder*>(aData);
+    Holder* holder = aData;
     txAXMLEventHandler* handler = *holder->mHandler;
-    txOutputTransaction* transaction =
-        static_cast<txOutputTransaction*>(aElement);
+    txOutputTransaction* transaction = aElement;
 
     nsresult rv;
     switch (transaction->mType) {
@@ -474,7 +468,11 @@ txResultBuffer::flushToHandler(txAXMLEventHandler** aHandler)
     Holder data = { aHandler, NS_OK };
     mStringValue.BeginReading(data.mIter);
 
-    mTransactions.EnumerateForwards(flushTransaction, &data);
+    for (PRUint32 i, len = mTransactions.Length(); i < len; ++i) {
+        if (!flushTransaction(mTransactions[i], &data)) {
+            break;
+        }
+    }
 
     return data.mResult;
 }
@@ -482,9 +480,9 @@ txResultBuffer::flushToHandler(txAXMLEventHandler** aHandler)
 txOutputTransaction*
 txResultBuffer::getLastTransaction()
 {
-    PRInt32 last = mTransactions.Count() - 1;
+    PRInt32 last = mTransactions.Length() - 1;
     if (last < 0) {
         return nsnull;
     }
-    return static_cast<txOutputTransaction*>(mTransactions[last]);
+    return mTransactions[last];
 }
diff --git a/content/xslt/src/xslt/txBufferingHandler.h b/content/xslt/src/xslt/txBufferingHandler.h
index 8d298568b9fe..72c20dbc286e 100644
--- a/content/xslt/src/xslt/txBufferingHandler.h
+++ b/content/xslt/src/xslt/txBufferingHandler.h
@@ -42,7 +42,7 @@
 
 #include "txXMLEventHandler.h"
 #include "nsString.h"
-#include "nsVoidArray.h"
+#include "nsTArray.h"
 #include "nsAutoPtr.h"
 
 class txOutputTransaction;
@@ -67,7 +67,7 @@ public:
     nsString mStringValue;
 
 private:
-    nsVoidArray mTransactions;
+    nsTArray<txOutputTransaction*> mTransactions;
 };
 
 class txBufferingHandler : public txAXMLEventHandler
diff --git a/content/xslt/src/xslt/txExecutionState.h b/content/xslt/src/xslt/txExecutionState.h
index 2975780320b3..a1d86a5c8309 100644
--- a/content/xslt/src/xslt/txExecutionState.h
+++ b/content/xslt/src/xslt/txExecutionState.h
@@ -42,7 +42,6 @@
 #include "txCore.h"
 #include "txStack.h"
 #include "txXMLUtils.h"
-#include "nsVoidArray.h"
 #include "txIXPathContext.h"
 #include "txVariableMap.h"
 #include "nsTHashtable.h"
diff --git a/content/xslt/src/xslt/txInstructions.cpp b/content/xslt/src/xslt/txInstructions.cpp
index 2bfe93cdf0a6..53346eb43b4e 100644
--- a/content/xslt/src/xslt/txInstructions.cpp
+++ b/content/xslt/src/xslt/txInstructions.cpp
@@ -642,10 +642,10 @@ txPushNewContext::txPushNewContext(nsAutoPtr<Expr> aSelect)
 
 txPushNewContext::~txPushNewContext()
 {
-    PRInt32 i;
-    for (i = 0; i < mSortKeys.Count(); ++i)
+    PRUint32 i;
+    for (i = 0; i < mSortKeys.Length(); ++i)
     {
-        delete static_cast<SortKey*>(mSortKeys[i]);
+        delete mSortKeys[i];
     }
 }
 
@@ -673,9 +673,9 @@ txPushNewContext::execute(txExecutionState& aEs)
     }
 
     txNodeSorter sorter;
-    PRInt32 i, count = mSortKeys.Count();
+    PRUint32 i, count = mSortKeys.Length();
     for (i = 0; i < count; ++i) {
-        SortKey* sort = static_cast<SortKey*>(mSortKeys[i]);
+        SortKey* sort = mSortKeys[i];
         rv = sorter.addSortElement(sort->mSelectExpr, sort->mLangExpr,
                                    sort->mDataTypeExpr, sort->mOrderExpr,
                                    sort->mCaseOrderExpr,
@@ -711,7 +711,7 @@ txPushNewContext::addSort(nsAutoPtr<Expr> aSelectExpr,
                                 aOrderExpr, aCaseOrderExpr);
     NS_ENSURE_TRUE(sort, NS_ERROR_OUT_OF_MEMORY);
 
-    if (!mSortKeys.AppendElement(sort)) {
+    if (mSortKeys.AppendElement(sort) == nsnull) {
         delete sort;
         return NS_ERROR_OUT_OF_MEMORY;
     }
diff --git a/content/xslt/src/xslt/txInstructions.h b/content/xslt/src/xslt/txInstructions.h
index 4079217daec2..c5344794f0b7 100644
--- a/content/xslt/src/xslt/txInstructions.h
+++ b/content/xslt/src/xslt/txInstructions.h
@@ -46,6 +46,7 @@
 #include "txNamespaceMap.h"
 #include "nsAutoPtr.h"
 #include "txXSLTNumber.h"
+#include "nsTArray.h"
 
 class nsIAtom;
 class txExecutionState;
@@ -304,7 +305,7 @@ public:
         nsAutoPtr<Expr> mCaseOrderExpr;
     };
     
-    nsVoidArray mSortKeys;
+    nsTArray<SortKey*> mSortKeys;
     nsAutoPtr<Expr> mSelect;
     txInstruction* mBailTarget;
 };
diff --git a/content/xslt/src/xslt/txStylesheetCompiler.cpp b/content/xslt/src/xslt/txStylesheetCompiler.cpp
index b8bde51c0a01..759c5cb4306d 100644
--- a/content/xslt/src/xslt/txStylesheetCompiler.cpp
+++ b/content/xslt/src/xslt/txStylesheetCompiler.cpp
@@ -229,8 +229,8 @@ txStylesheetCompiler::startElementInternal(PRInt32 aNamespaceID,
 {
     nsresult rv = NS_OK;
     PRInt32 i;
-    for (i = mInScopeVariables.Count() - 1; i >= 0; --i) {
-        ++(static_cast<txInScopeVariable*>(mInScopeVariables[i]))->mLevel;
+    for (i = mInScopeVariables.Length() - 1; i >= 0; --i) {
+        ++mInScopeVariables[i]->mLevel;
     }
 
     // Update the elementcontext if we have special attributes
@@ -287,7 +287,7 @@ txStylesheetCompiler::startElementInternal(PRInt32 aNamespaceID,
                     return NS_ERROR_XSLT_PARSE_FAILURE;
 
                 if (!mElementContext->mInstructionNamespaces.
-                        AppendElement(NS_INT32_TO_PTR(namespaceID))) {
+                        AppendElement(namespaceID)) {
                     return NS_ERROR_OUT_OF_MEMORY;
                 }
             }
@@ -318,10 +318,9 @@ txStylesheetCompiler::startElementInternal(PRInt32 aNamespaceID,
 
     // Find the right elementhandler and execute it
     MBool isInstruction = MB_FALSE;
-    PRInt32 count = mElementContext->mInstructionNamespaces.Count();
+    PRInt32 count = mElementContext->mInstructionNamespaces.Length();
     for (i = 0; i < count; ++i) {
-        if (NS_PTR_TO_INT32(mElementContext->mInstructionNamespaces[i]) ==
-            aNamespaceID) {
+        if (mElementContext->mInstructionNamespaces[i] == aNamespaceID) {
             isInstruction = MB_TRUE;
             break;
         }
@@ -381,9 +380,8 @@ txStylesheetCompiler::endElement()
     NS_ENSURE_SUCCESS(rv, rv);
 
     PRInt32 i;
-    for (i = mInScopeVariables.Count() - 1; i >= 0; --i) {
-        txInScopeVariable* var =
-            static_cast<txInScopeVariable*>(mInScopeVariables[i]);
+    for (i = mInScopeVariables.Length() - 1; i >= 0; --i) {
+        txInScopeVariable* var = mInScopeVariables[i];
         if (!--(var->mLevel)) {
             nsAutoPtr<txInstruction> instr(new txRemoveVariable(var->mName));
             NS_ENSURE_TRUE(instr, NS_ERROR_OUT_OF_MEMORY);
@@ -544,7 +542,7 @@ txStylesheetCompiler::ensureNewElementContext()
 nsresult
 txStylesheetCompiler::maybeDoneCompiling()
 {
-    if (!mDoneWithThisStylesheet || mChildCompilerList.Count()) {
+    if (!mDoneWithThisStylesheet || !mChildCompilerList.IsEmpty()) {
         return NS_OK;
     }
     
@@ -647,8 +645,8 @@ txStylesheetCompilerState::~txStylesheetCompilerState()
     }
     
     PRInt32 i;
-    for (i = mInScopeVariables.Count() - 1; i >= 0; --i) {
-        delete static_cast<txInScopeVariable*>(mInScopeVariables[i]);
+    for (i = mInScopeVariables.Length() - 1; i >= 0; --i) {
+        delete mInScopeVariables[i];
     }
 }
 
@@ -755,7 +753,7 @@ txStylesheetCompilerState::openInstructionContainer(txInstructionContainer* aCon
 void
 txStylesheetCompilerState::closeInstructionContainer()
 {
-    NS_ASSERTION(mGotoTargetPointers.Count() == 0,
+    NS_ASSERTION(mGotoTargetPointers.IsEmpty(),
                  "GotoTargets still exists, did you forget to add txReturn?");
     mNextInstrPtr = 0;
 }
@@ -770,9 +768,9 @@ txStylesheetCompilerState::addInstruction(nsAutoPtr<txInstruction> aInstruction)
     *mNextInstrPtr = aInstruction.forget();
     mNextInstrPtr = newInstr->mNext.StartAssignment();
     
-    PRInt32 i, count = mGotoTargetPointers.Count();
+    PRUint32 i, count = mGotoTargetPointers.Length();
     for (i = 0; i < count; ++i) {
-        *static_cast<txInstruction**>(mGotoTargetPointers[i]) = newInstr;
+        *mGotoTargetPointers[i] = newInstr;
     }
     mGotoTargetPointers.Clear();
 
@@ -811,7 +809,7 @@ txStylesheetCompilerState::loadIncludedStylesheet(const nsAString& aURI)
     // step forward before calling the observer in case of syncronous loading
     mToplevelIterator.next();
 
-    if (!mChildCompilerList.AppendElement(compiler)) {
+    if (mChildCompilerList.AppendElement(compiler) == nsnull) {
         return NS_ERROR_OUT_OF_MEMORY;
     }
 
@@ -844,7 +842,7 @@ txStylesheetCompilerState::loadImportedStylesheet(const nsAString& aURI,
         new txStylesheetCompiler(aURI, mStylesheet, &iter, observer);
     NS_ENSURE_TRUE(compiler, NS_ERROR_OUT_OF_MEMORY);
 
-    if (!mChildCompilerList.AppendElement(compiler)) {
+    if (mChildCompilerList.AppendElement(compiler) == nsnull) {
         return NS_ERROR_OUT_OF_MEMORY;
     }
 
@@ -859,7 +857,7 @@ txStylesheetCompilerState::loadImportedStylesheet(const nsAString& aURI,
 nsresult
 txStylesheetCompilerState::addGotoTarget(txInstruction** aTargetPointer)
 {
-    if (!mGotoTargetPointers.AppendElement(aTargetPointer)) {
+    if (mGotoTargetPointers.AppendElement(aTargetPointer) == nsnull) {
         return NS_ERROR_OUT_OF_MEMORY;
     }
     
@@ -1162,7 +1160,7 @@ txElementContext::txElementContext(const nsAString& aBaseURI)
       mMappings(new txNamespaceMap),
       mDepth(0)
 {
-    mInstructionNamespaces.AppendElement(NS_INT32_TO_PTR(kNameSpaceID_XSLT));
+    mInstructionNamespaces.AppendElement(kNameSpaceID_XSLT);
 }
 
 txElementContext::txElementContext(const txElementContext& aOther)
diff --git a/content/xslt/src/xslt/txStylesheetCompiler.h b/content/xslt/src/xslt/txStylesheetCompiler.h
index fc1173daac3b..fc23fb4d3d89 100644
--- a/content/xslt/src/xslt/txStylesheetCompiler.h
+++ b/content/xslt/src/xslt/txStylesheetCompiler.h
@@ -45,6 +45,7 @@
 #include "txIXPathContext.h"
 #include "nsAutoPtr.h"
 #include "txStylesheet.h"
+#include "nsTArray.h"
 
 extern PRBool
 TX_XSLTFunctionAvailable(nsIAtom* aName, PRInt32 aNameSpaceID);
@@ -57,6 +58,7 @@ class txNamespaceMap;
 class txToplevelItem;
 class txPushNewContext;
 class txStylesheetCompiler;
+class txInScopeVariable;
 
 class txElementContext : public TxObject
 {
@@ -68,7 +70,7 @@ public:
     PRBool mForwardsCompatibleParsing;
     nsString mBaseURI;
     nsRefPtr<txNamespaceMap> mMappings;
-    nsVoidArray mInstructionNamespaces;
+    nsTArray<PRInt32> mInstructionNamespaces;
     PRInt32 mDepth;
 };
 
@@ -169,8 +171,8 @@ public:
 
 protected:
     nsRefPtr<txACompileObserver> mObserver;
-    nsVoidArray mInScopeVariables;
-    nsVoidArray mChildCompilerList;
+    nsTArray<txInScopeVariable*> mInScopeVariables;
+    nsTArray<txStylesheetCompiler*> mChildCompilerList;
     // embed info, target information is the ID
     nsString mTarget;
     enum 
@@ -189,7 +191,7 @@ protected:
 private:
     txInstruction** mNextInstrPtr;
     txListIterator mToplevelIterator;
-    nsVoidArray mGotoTargetPointers;
+    nsTArray<txInstruction**> mGotoTargetPointers;
 };
 
 struct txStylesheetAttr
diff --git a/content/xslt/src/xslt/txXSLTPatterns.h b/content/xslt/src/xslt/txXSLTPatterns.h
index 707a55e1ee0c..0b4e195276d8 100644
--- a/content/xslt/src/xslt/txXSLTPatterns.h
+++ b/content/xslt/src/xslt/txXSLTPatterns.h
@@ -41,7 +41,6 @@
 
 #include "txExpr.h"
 #include "txXMLUtils.h"
-#include "nsVoidArray.h"
 
 class ProcessorState;
 
diff --git a/content/xul/document/src/nsXULContentSink.h b/content/xul/document/src/nsXULContentSink.h
index 1285d1a5157e..f5ea8e4e7bfa 100644
--- a/content/xul/document/src/nsXULContentSink.h
+++ b/content/xul/document/src/nsXULContentSink.h
@@ -46,7 +46,6 @@
 #include "nsIXMLContentSink.h"
 #include "nsAutoPtr.h"
 #include "nsNodeInfoManager.h"
-#include "nsVoidArray.h"
 #include "nsWeakPtr.h"
 #include "nsXULElement.h"
 
diff --git a/content/xul/document/src/nsXULControllers.cpp b/content/xul/document/src/nsXULControllers.cpp
index 3af8d9cc2af5..878ecb417482 100644
--- a/content/xul/document/src/nsXULControllers.cpp
+++ b/content/xul/document/src/nsXULControllers.cpp
@@ -67,10 +67,10 @@ nsXULControllers::~nsXULControllers(void)
 void
 nsXULControllers::DeleteControllers()
 {
-  PRUint32 count = mControllers.Count();
+  PRUint32 count = mControllers.Length();
   for (PRUint32 i = 0; i < count; i++)
   {
-    nsXULControllerData*  controllerData = static_cast<nsXULControllerData*>(mControllers.ElementAt(i));
+    nsXULControllerData* controllerData = mControllers.ElementAt(i);
     if (controllerData)
       delete controllerData;    // releases the nsIController
   }
@@ -103,10 +103,9 @@ NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(nsXULControllers)
 NS_IMPL_CYCLE_COLLECTION_UNLINK_END
 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(nsXULControllers)
   {
-    PRUint32 i, count = tmp->mControllers.Count();
+    PRUint32 i, count = tmp->mControllers.Length();
     for (i = 0; i < count; ++i) {
-      nsXULControllerData*  controllerData =
-        static_cast<nsXULControllerData*>(tmp->mControllers[i]);
+      nsXULControllerData* controllerData = tmp->mControllers[i];
       if (controllerData) {
         cb.NoteXPCOMChild(controllerData->mController);
       }
@@ -130,10 +129,10 @@ nsXULControllers::GetControllerForCommand(const char *aCommand, nsIController**
   NS_ENSURE_ARG_POINTER(_retval);
   *_retval = nsnull;
 
-  PRUint32 count = mControllers.Count();
+  PRUint32 count = mControllers.Length();
   for (PRUint32 i=0; i < count; i++)
   {
-    nsXULControllerData*  controllerData = static_cast<nsXULControllerData*>(mControllers.ElementAt(i));
+    nsXULControllerData* controllerData = mControllers.ElementAt(i);
     if (controllerData)
     {
       nsCOMPtr<nsIController> controller;
@@ -160,10 +159,10 @@ nsXULControllers::InsertControllerAt(PRUint32 aIndex, nsIController *controller)
   nsXULControllerData*  controllerData = new nsXULControllerData(++mCurControllerID, controller);
   if (!controllerData) return NS_ERROR_OUT_OF_MEMORY;
 #ifdef DEBUG
-  PRBool inserted =
+  nsXULControllerData** inserted =
 #endif
-  mControllers.InsertElementAt((void *)controllerData, aIndex);
-  NS_ASSERTION(inserted, "Insertion of controller failed");
+  mControllers.InsertElementAt(aIndex, controllerData);
+  NS_ASSERTION(inserted != nsnull, "Insertion of controller failed");
   return NS_OK;
 }
 
@@ -173,14 +172,10 @@ nsXULControllers::RemoveControllerAt(PRUint32 aIndex, nsIController **_retval)
   NS_ENSURE_ARG_POINTER(_retval);
   *_retval = nsnull;
 
-  nsXULControllerData*  controllerData = static_cast<nsXULControllerData*>(mControllers.SafeElementAt(aIndex));
+  nsXULControllerData* controllerData = mControllers.SafeElementAt(aIndex);
   if (!controllerData) return NS_ERROR_FAILURE;
 
-#ifdef DEBUG
-  PRBool removed =
-#endif
   mControllers.RemoveElementAt(aIndex);
-  NS_ASSERTION(removed, "Removal of controller failed");
 
   controllerData->GetController(_retval);
   delete controllerData;
@@ -195,7 +190,7 @@ nsXULControllers::GetControllerAt(PRUint32 aIndex, nsIController **_retval)
   NS_ENSURE_ARG_POINTER(_retval);
   *_retval = nsnull;
 
-  nsXULControllerData*  controllerData = static_cast<nsXULControllerData*>(mControllers.SafeElementAt(aIndex));
+  nsXULControllerData* controllerData = mControllers.SafeElementAt(aIndex);
   if (!controllerData) return NS_ERROR_FAILURE;
 
   return controllerData->GetController(_retval);   // does the addref  
@@ -209,10 +204,10 @@ nsXULControllers::AppendController(nsIController *controller)
   if (!controllerData) return NS_ERROR_OUT_OF_MEMORY;
 
 #ifdef DEBUG
-  PRBool appended =
+  nsXULControllerData** appended =
 #endif
-  mControllers.AppendElement((void *)controllerData);
-  NS_ASSERTION(appended, "Appending controller failed");
+  mControllers.AppendElement(controllerData);
+  NS_ASSERTION(appended != nsnull, "Appending controller failed");
   return NS_OK;
 }
 
@@ -222,10 +217,10 @@ nsXULControllers::RemoveController(nsIController *controller)
   // first get the identity pointer
   nsCOMPtr<nsISupports> controllerSup(do_QueryInterface(controller));
   // then find it
-  PRUint32 count = mControllers.Count();
+  PRUint32 count = mControllers.Length();
   for (PRUint32 i = 0; i < count; i++)
   {
-    nsXULControllerData*  controllerData = static_cast<nsXULControllerData*>(mControllers.ElementAt(i));
+    nsXULControllerData* controllerData = mControllers.ElementAt(i);
     if (controllerData)
     {
       nsCOMPtr<nsIController> thisController;
@@ -248,10 +243,10 @@ nsXULControllers::GetControllerId(nsIController *controller, PRUint32 *_retval)
 {
   NS_ENSURE_ARG_POINTER(_retval);
 
-  PRUint32 count = mControllers.Count();
+  PRUint32 count = mControllers.Length();
   for (PRUint32 i = 0; i < count; i++)
   {
-    nsXULControllerData*  controllerData = static_cast<nsXULControllerData*>(mControllers.ElementAt(i));
+    nsXULControllerData* controllerData = mControllers.ElementAt(i);
     if (controllerData)
     {
       nsCOMPtr<nsIController> thisController;
@@ -272,10 +267,10 @@ nsXULControllers::GetControllerById(PRUint32 controllerID, nsIController **_retv
 {
   NS_ENSURE_ARG_POINTER(_retval);
     
-  PRUint32 count = mControllers.Count();
+  PRUint32 count = mControllers.Length();
   for (PRUint32 i = 0; i < count; i++)
   {
-    nsXULControllerData*  controllerData = static_cast<nsXULControllerData*>(mControllers.ElementAt(i));
+    nsXULControllerData* controllerData = mControllers.ElementAt(i);
     if (controllerData && controllerData->GetControllerID() == controllerID)
     {
       return controllerData->GetController(_retval);
@@ -288,7 +283,7 @@ NS_IMETHODIMP
 nsXULControllers::GetControllerCount(PRUint32 *_retval)
 {
   NS_ENSURE_ARG_POINTER(_retval);
-  *_retval = mControllers.Count();
+  *_retval = mControllers.Length();
   return NS_OK;
 }
 
diff --git a/content/xul/document/src/nsXULControllers.h b/content/xul/document/src/nsXULControllers.h
index ce10e771f31a..d4d98a357880 100644
--- a/content/xul/document/src/nsXULControllers.h
+++ b/content/xul/document/src/nsXULControllers.h
@@ -46,7 +46,7 @@
 #define nsXULControllers_h__
 
 #include "nsCOMPtr.h"
-#include "nsVoidArray.h"
+#include "nsTPtrArray.h"
 #include "nsWeakPtr.h"
 #include "nsIControllers.h"
 #include "nsISecurityCheckedComponent.h"
@@ -97,8 +97,8 @@ protected:
 
     void        DeleteControllers();
 
-    nsVoidArray mControllers;
-    PRUint32    mCurControllerID;
+    nsTPtrArray<nsXULControllerData> mControllers;
+    PRUint32                         mCurControllerID;
 };
 
 
diff --git a/content/xul/templates/src/nsTemplateRule.h b/content/xul/templates/src/nsTemplateRule.h
index fd645084cb4a..e8273134b166 100644
--- a/content/xul/templates/src/nsTemplateRule.h
+++ b/content/xul/templates/src/nsTemplateRule.h
@@ -45,7 +45,6 @@
 #include "nsIRDFResource.h"
 #include "nsIContent.h"
 #include "nsIDOMNode.h"
-#include "nsVoidArray.h"
 #include "nsTArray.h"
 #include "nsString.h"
 #include "nsIXULTemplateRuleFilter.h"
@@ -277,7 +276,7 @@ protected:
 class nsTemplateQuerySet
 {
 protected:
-    nsVoidArray mRules; // rules owned by nsTemplateQuerySet
+    nsTArray<nsTemplateRule*> mRules; // rules owned by nsTemplateQuerySet
 
     // a number which increments for each successive queryset. It is stored so
     // it can be used as an optimization when updating results so that it is
@@ -321,28 +320,28 @@ public:
     {
         // nsTemplateMatch stores the index as a 16-bit value,
         // so check to make sure for overflow
-        if (mRules.Count() == PR_INT16_MAX)
+        if (mRules.Length() == PR_INT16_MAX)
             return NS_ERROR_FAILURE;
 
-        if (!mRules.AppendElement(aChild))
+        if (mRules.AppendElement(aChild) == nsnull)
             return NS_ERROR_OUT_OF_MEMORY;
         return NS_OK;
     }
 
     PRInt16 RuleCount() const
     {
-        return mRules.Count();
+        return mRules.Length();
     }
 
     nsTemplateRule* GetRuleAt(PRInt16 aIndex)
     {
-        return static_cast<nsTemplateRule*>(mRules[aIndex]);
+        return mRules[aIndex];
     }
 
     void Clear()
     {
-        for (PRInt32 r = mRules.Count() - 1; r >= 0; r--) {
-            nsTemplateRule* rule = static_cast<nsTemplateRule*>(mRules[r]);
+        for (PRInt32 r = mRules.Length() - 1; r >= 0; r--) {
+            nsTemplateRule* rule = mRules[r];
             delete rule;
         }
         mRules.Clear();
diff --git a/content/xul/templates/src/nsXULContentBuilder.cpp b/content/xul/templates/src/nsXULContentBuilder.cpp
index 9c780b2a1b33..91dfea86656f 100644
--- a/content/xul/templates/src/nsXULContentBuilder.cpp
+++ b/content/xul/templates/src/nsXULContentBuilder.cpp
@@ -54,7 +54,7 @@
 #include "nsXULSortService.h"
 #include "nsTemplateRule.h"
 #include "nsTemplateMap.h"
-#include "nsVoidArray.h"
+#include "nsTArray.h"
 #include "nsXPIDLString.h"
 #include "nsGkAtoms.h"
 #include "nsXULContentUtils.h"
@@ -1323,15 +1323,15 @@ nsXULContentBuilder::RemoveGeneratedContent(nsIContent* aElement)
 {
     // Keep a queue of "ungenerated" elements that we have to probe
     // for generated content.
-    nsAutoVoidArray ungenerated;
-    if (!ungenerated.AppendElement(aElement))
+    nsAutoTArray<nsIContent*, 8> ungenerated;
+    if (ungenerated.AppendElement(aElement) == nsnull)
         return NS_ERROR_OUT_OF_MEMORY;
 
-    PRInt32 count;
-    while (0 != (count = ungenerated.Count())) {
+    PRUint32 count;
+    while (0 != (count = ungenerated.Length())) {
         // Pull the next "ungenerated" element off the queue.
-        PRInt32 last = count - 1;
-        nsIContent* element = static_cast<nsIContent*>(ungenerated[last]);
+        PRUint32 last = count - 1;
+        nsIContent* element = ungenerated[last];
         ungenerated.RemoveElementAt(last);
 
         PRUint32 i = element->GetChildCount();
@@ -1357,7 +1357,7 @@ nsXULContentBuilder::RemoveGeneratedContent(nsIContent* aElement)
             if (! tmpl) {
                 // No 'template' attribute, so this must not have been
                 // generated. We'll need to examine its kids.
-                if (!ungenerated.AppendElement(child))
+                if (ungenerated.AppendElement(child) == nsnull)
                     return NS_ERROR_OUT_OF_MEMORY;
                 continue;
             }
diff --git a/content/xul/templates/src/nsXULTemplateBuilder.cpp b/content/xul/templates/src/nsXULTemplateBuilder.cpp
index a2eb62a953ff..8d11931708bd 100644
--- a/content/xul/templates/src/nsXULTemplateBuilder.cpp
+++ b/content/xul/templates/src/nsXULTemplateBuilder.cpp
@@ -89,7 +89,7 @@
 #include "nsRDFCID.h"
 #include "nsXULContentUtils.h"
 #include "nsString.h"
-#include "nsVoidArray.h"
+#include "nsTArray.h"
 #include "nsXPIDLString.h"
 #include "nsWhitespaceTokenizer.h"
 #include "nsGkAtoms.h"
@@ -2488,15 +2488,15 @@ nsXULTemplateBuilder::AddSimpleRuleBindings(nsTemplateRule* aRule,
     // Crawl the content tree of a "simple" rule, adding a variable
     // assignment for any attribute whose value is "rdf:".
 
-    nsAutoVoidArray elements;
+    nsAutoTArray<nsIContent*, 8> elements;
 
-    if (!elements.AppendElement(aElement))
+    if (elements.AppendElement(aElement) == nsnull)
         return NS_ERROR_OUT_OF_MEMORY;
 
-    while (elements.Count()) {
+    while (elements.Length()) {
         // Pop the next element off the stack
-        PRUint32 i = (PRUint32)(elements.Count() - 1);
-        nsIContent* element = static_cast<nsIContent*>(elements[i]);
+        PRUint32 i = elements.Length() - 1;
+        nsIContent* element = elements[i];
         elements.RemoveElementAt(i);
 
         // Iterate through its attributes, looking for substitutions
@@ -2521,7 +2521,7 @@ nsXULTemplateBuilder::AddSimpleRuleBindings(nsTemplateRule* aRule,
         count = element->GetChildCount();
 
         while (count-- > 0) {
-            if (!elements.AppendElement(element->GetChildAt(count)))
+            if (elements.AppendElement(element->GetChildAt(count)) == nsnull)
                 return NS_ERROR_OUT_OF_MEMORY;
         }
     }
diff --git a/content/xul/templates/src/nsXULTemplateBuilder.h b/content/xul/templates/src/nsXULTemplateBuilder.h
index ea32001c21fe..c513324e158c 100644
--- a/content/xul/templates/src/nsXULTemplateBuilder.h
+++ b/content/xul/templates/src/nsXULTemplateBuilder.h
@@ -56,7 +56,6 @@
 #include "nsIXULTemplateBuilder.h"
 
 #include "nsFixedSizeAllocator.h"
-#include "nsVoidArray.h"
 #include "nsCOMArray.h"
 #include "nsTArray.h"
 #include "nsDataHashtable.h"
diff --git a/content/xul/templates/src/nsXULTemplateQueryProcessorRDF.h b/content/xul/templates/src/nsXULTemplateQueryProcessorRDF.h
index 10fafba235eb..5dd40d98dbea 100644
--- a/content/xul/templates/src/nsXULTemplateQueryProcessorRDF.h
+++ b/content/xul/templates/src/nsXULTemplateQueryProcessorRDF.h
@@ -61,7 +61,6 @@
 #include "nsRDFQuery.h"
 #include "nsRDFBinding.h"
 #include "nsXULTemplateResultSetRDF.h"
-#include "nsVoidArray.h"
 #include "nsCOMArray.h"
 #include "nsIArray.h"
 #include "nsString.h"
diff --git a/content/xul/templates/src/nsXULTreeBuilder.cpp b/content/xul/templates/src/nsXULTreeBuilder.cpp
index 4712d2cc7dcd..e8a3d3bb2d87 100644
--- a/content/xul/templates/src/nsXULTreeBuilder.cpp
+++ b/content/xul/templates/src/nsXULTreeBuilder.cpp
@@ -59,7 +59,7 @@
 #include "nsGkAtoms.h"
 #include "nsXULContentUtils.h"
 #include "nsXULTemplateBuilder.h"
-#include "nsVoidArray.h"
+#include "nsTArray.h"
 #include "nsUnicharUtils.h"
 #include "nsINameSpaceManager.h"
 #include "nsIDOMClassInfo.h"
@@ -152,7 +152,7 @@ protected:
                            nsIXULTemplateResult *aResult,
                            nsTemplateQuerySet* aQuerySet,
                            PRInt32* aDelta,
-                           nsAutoVoidArray& open);
+                           nsTArray<PRInt32>& open);
 
     /**
      * Close a container row, removing the container's childrem from
@@ -1522,7 +1522,7 @@ nsXULTreeBuilder::OpenSubtreeOf(nsTreeRows::Subtree* aSubtree,
                                 nsIXULTemplateResult *aResult,
                                 PRInt32* aDelta)
 {
-    nsAutoVoidArray open;
+    nsAutoTArray<PRInt32, 8> open;
     PRInt32 count = 0;
 
     PRInt32 rulecount = mQuerySets.Length();
@@ -1534,8 +1534,8 @@ nsXULTreeBuilder::OpenSubtreeOf(nsTreeRows::Subtree* aSubtree,
 
     // Now recursively deal with any open sub-containers that just got
     // inserted. We need to do this back-to-front to avoid skewing offsets.
-    for (PRInt32 i = open.Count() - 1; i >= 0; --i) {
-        PRInt32 index = NS_PTR_TO_INT32(open[i]);
+    for (PRInt32 i = open.Length() - 1; i >= 0; --i) {
+        PRInt32 index = open[i];
 
         nsTreeRows::Subtree* child =
             mRows.EnsureSubtreeFor(aSubtree, index);
@@ -1566,7 +1566,7 @@ nsXULTreeBuilder::OpenSubtreeForQuerySet(nsTreeRows::Subtree* aSubtree,
                                          nsIXULTemplateResult* aResult,
                                          nsTemplateQuerySet* aQuerySet,
                                          PRInt32* aDelta,
-                                         nsAutoVoidArray& open)
+                                         nsTArray<PRInt32>& open)
 {
     PRInt32 count = *aDelta;
     
@@ -1674,7 +1674,7 @@ nsXULTreeBuilder::OpenSubtreeForQuerySet(nsTreeRows::Subtree* aSubtree,
                 PRBool isOpen = PR_FALSE;
                 IsContainerOpen(nextresult, &isOpen);
                 if (isOpen) {
-                    if (!open.AppendElement(NS_INT32_TO_PTR(count)))
+                    if (open.AppendElement(count) == nsnull)
                         return NS_ERROR_OUT_OF_MEMORY;
                 }