diff --git a/layout/html/base/src/nsScrollFrame.cpp b/layout/html/base/src/nsScrollFrame.cpp
index a6831eb6fc7..16ce7a0c509 100644
--- a/layout/html/base/src/nsScrollFrame.cpp
+++ b/layout/html/base/src/nsScrollFrame.cpp
@@ -34,6 +34,7 @@
 #include "nsScrollFrame.h"
 #include "nsLayoutAtoms.h"
 #include "nsIWebShell.h"
+#include "nsIBox.h"
 
 static NS_DEFINE_IID(kIWebShellIID, NS_IWEB_SHELL_IID);
 
@@ -577,7 +578,16 @@ nsScrollFrame::Reflow(nsIPresContext&          aPresContext,
   // Reflow the child and get its desired size. Let it be as high as it
   // wants
   PRBool              unconstrainedWidth = (NS_UNCONSTRAINEDSIZE == scrollAreaSize.width);
-  nsSize              kidReflowSize(scrollAreaSize.width, NS_UNCONSTRAINEDSIZE);
+
+  nscoord theHeight;
+  nsIBox* box;
+  nsresult result = kidFrame->QueryInterface(kIBoxIID, (void**)&box);
+  if (NS_SUCCEEDED(result))
+     theHeight = scrollAreaSize.height;
+  else 
+     theHeight = NS_INTRINSICSIZE;
+
+  nsSize              kidReflowSize(scrollAreaSize.width, theHeight);
   nsHTMLReflowState   kidReflowState(aPresContext, aReflowState,
                                      kidFrame, kidReflowSize);
   nsHTMLReflowMetrics kidDesiredSize(aDesiredSize.maxElementSize);
@@ -589,7 +599,7 @@ nsScrollFrame::Reflow(nsIPresContext&          aPresContext,
                                     aReflowState.mComputedPadding.left -
                                     aReflowState.mComputedPadding.right;
   }
-  kidReflowState.mComputedHeight = NS_AUTOHEIGHT;
+  kidReflowState.mComputedHeight = theHeight;
 
   ReflowChild(kidFrame, aPresContext, kidDesiredSize, kidReflowState,
               aStatus);
diff --git a/layout/xul/base/src/nsBoxFrame.cpp b/layout/xul/base/src/nsBoxFrame.cpp
index 47fba4d2c26..7e1df99ab59 100644
--- a/layout/xul/base/src/nsBoxFrame.cpp
+++ b/layout/xul/base/src/nsBoxFrame.cpp
@@ -55,6 +55,7 @@ public:
   void DrawVerticalSpring( nsIPresContext& aPresContext, nsIRenderingContext& aRenderingContext, nscoord x, nscoord y, nscoord size, nscoord springSize);
   void DrawKnob( nsIPresContext& aPresContext, nsIRenderingContext& aRenderingContext, nscoord x, nscoord y, nscoord springSize);
   void AddInDebugInset( nsIPresContext& aPresContext, PRBool aIsHorizontal, nsMargin& inset);
+  void CollapseChild(nsIFrame* frame);
 
     // XXX for the moment we can only handle 100 children.
     // Should use a dynamic array.
@@ -191,6 +192,20 @@ nsBoxFrame::GetRedefinedMinPrefMax(nsIFrame* aFrame, nsCalculatedBoxInfo& aSize)
         // convert to a percent.
         aSize.flex = value.ToFloat(&error)/float(100.0);
     }
+
+    if (NS_CONTENT_ATTR_HAS_VALUE == content->GetAttribute(kNameSpaceID_None, nsHTMLAtoms::width, value))
+    {
+        value.Trim("%");
+        // convert to a percent.
+        aSize.prefSize.width = value.ToInteger(&error);
+    }
+
+    if (NS_CONTENT_ATTR_HAS_VALUE == content->GetAttribute(kNameSpaceID_None, nsHTMLAtoms::height, value))
+    {
+        value.Trim("%");
+        // convert to a percent.
+        aSize.prefSize.height = value.ToInteger(&error);
+    }
 }
 
 /**
@@ -705,29 +720,38 @@ nsBoxFrame::ChildResized(nsHTMLReflowMetrics& aDesiredSize, nsRect& aRect, nsCal
 }
 
 
-/*
 void 
-nsBoxFrameImpl::CollapseChildren(nsIFrame* frame)
+nsBoxFrameImpl::CollapseChild(nsIFrame* frame)
 {
-  nscoord count = 0;
-  while (nsnull != frame) 
-  {
     nsRect rect(0,0,0,0);
-    childFrame->SetRect(nsRect(0,0,0,0));
-    // make the view really small as well
-    nsIView* view = nsnull;
-    childFrame->GetView(&view);
+    frame->GetRect(rect);
+    if (rect.width > 0 || rect.height > 0) {
+      // shrink the frame
+      frame->SizeTo(0,0);
 
-    if (view) {
-      view->SetDimensions(0,0,PR_FALSE);
+      // shrink the view
+      nsIView* view = nsnull;
+      frame->GetView(&view);
+
+      // if we find a view stop right here. All views under it
+      // will be clipped.
+      if (view) {
+        view->SetDimensions(0,0,PR_FALSE);
+        return;
+      }
+    
+      // collapse the child
+      nsIFrame* child = nsnull;
+      frame->FirstChild(nsnull, &child);
+
+      while (nsnull != child) 
+      {
+         CollapseChild(child);
+         nsresult rv = child->GetNextSibling(&child);
+         NS_ASSERTION(rv == NS_OK,"failed to get next child");
+      }
     }
- 
-    CollapseChildren(childFrame);
-    rv = childFrame->GetNextSibling(&childFrame);
-    NS_ASSERTION(rv == NS_OK,"failed to get next child");
-  }
 }
-*/
 
 
 /**
@@ -749,17 +773,7 @@ nsBoxFrame::PlaceChildren(nsRect& boxRect)
 
     // make collapsed children not show up
     if (mSprings[count].collapsed) {
-      childFrame->SetRect(nsRect(0,0,0,0));
-
-      // make the view really small as well
-      nsIView* view = nsnull;
-      childFrame->GetView(&view);
-
-      if (view) {
-        nsCOMPtr<nsIViewManager> vm;
-        view->GetViewManager(*getter_AddRefs(vm));
-        vm->ResizeView(view, 0,0);
-      }
+      mImpl->CollapseChild(childFrame);
     } else {
       const nsStyleSpacing* spacing;
       rv = childFrame->GetStyleData(eStyleStruct_Spacing,
@@ -1229,6 +1243,56 @@ nsBoxFrame::LayoutChildrenInRect(nsRect& size)
         }
 }
 
+/**
+ * Ok if we want to resize a child we will know the actual size in pixels we want it to be.
+ * This is not the preferred size. But they only way we can change a child is my manipulating its
+ * preferred size. So give the actual pixel size this return method will return figure out the preferred
+ * size and set it.
+ */
+void
+nsBoxFrame::ResizeChildTo(nscoord aChildIndex, nscoord aNewSize)
+{
+  // get all the variables we need
+  nscoord min         = GET_WIDTH(mSprings[aChildIndex].minSize);
+  nscoord max         = GET_WIDTH(mSprings[aChildIndex].maxSize);
+  nscoord c           = GET_WIDTH(mSprings[aChildIndex].calculatedSize);
+  nscoord pref        = GET_WIDTH(mSprings[aChildIndex].prefSize);
+  float flex          = mSprings[aChildIndex].flex;
+  float stretchFactor = float(c-pref)/flex;
+
+  // check bounds
+  if (aNewSize < min)
+     aNewSize = min;
+  else if (aNewSize > max)
+     aNewSize = max;
+
+  // determine the new pref size
+  pref = aNewSize - NSToIntFloor(flex/stretchFactor);
+
+  // find the child at the index
+  nsIFrame* childFrame = mFrames.FirstChild(); 
+  nscoord count = 0;
+  while (nsnull != childFrame) 
+  {
+    if (count == aChildIndex)
+      break;
+
+    nsresult rv;
+    rv = childFrame->GetNextSibling(&childFrame);
+    NS_ASSERTION(rv == NS_OK,"failed to get next child");
+    count++;
+  }
+
+  nsCOMPtr<nsIContent> content;
+  childFrame->GetContent(getter_AddRefs(content));
+
+
+  // set its preferred size.
+  char ch[50];
+  sprintf(ch,"%d",pref);
+  content->SetAttribute(kNameSpaceID_None, nsHTMLAtoms::width, ch, PR_TRUE);
+}
+
 // Marks the frame as dirty and generates an incremental reflow
 // command targeted at this frame
 nsresult
diff --git a/layout/xul/base/src/nsBoxFrame.h b/layout/xul/base/src/nsBoxFrame.h
index 9683cd46984..bfebbd78648 100644
--- a/layout/xul/base/src/nsBoxFrame.h
+++ b/layout/xul/base/src/nsBoxFrame.h
@@ -107,7 +107,9 @@ public:
 
   NS_IMETHOD GetFrameName(nsString& aResult) const;
 
-  PRBool IsHorizontal() const { return mHorizontal; }
+  virtual PRBool IsHorizontal() const { return mHorizontal; }
+
+  virtual void ResizeChildTo(nscoord aChildIndex, nscoord aNewSize);
 
   
   NS_IMETHOD_(nsrefcnt) AddRef(void);
diff --git a/layout/xul/base/src/nsGrippyFrame.cpp b/layout/xul/base/src/nsGrippyFrame.cpp
index 4f1ffed25a8..06d9a64311f 100644
--- a/layout/xul/base/src/nsGrippyFrame.cpp
+++ b/layout/xul/base/src/nsGrippyFrame.cpp
@@ -36,10 +36,16 @@
 #include "nsHTMLAtoms.h"
 #include "nsXULAtoms.h"
 #include "nsIReflowCommand.h"
-#include "nsSliderFrame.h"
+//#include "nsSliderFrame.h"
 #include "nsIDOMElement.h"
 #include "nsIDOMDocument.h"
 #include "nsDocument.h"
+#include "nsHTMLParts.h"
+#include "nsIPresShell.h"
+#include "nsIView.h"
+#include "nsIViewManager.h"
+#include "nsHTMLContainerFrame.h"
+
 
 //
 // NS_NewToolbarFrame
@@ -65,7 +71,6 @@ NS_NewGrippyFrame ( nsIFrame** aNewFrame )
 nsGrippyFrame::nsGrippyFrame():mCollapsed(PR_FALSE)
 {
 }
-
 void
 nsGrippyFrame::MouseClicked(nsIPresContext& aPresContext) 
 {
@@ -113,8 +118,21 @@ nsGrippyFrame::MouseClicked(nsIPresContext& aPresContext)
   mCollapsedChild->SetAttribute(kNameSpaceID_None, nsHTMLAtoms::style, style, PR_TRUE);
 
   mCollapsed = !mCollapsed;
+
+  /*
+  nsCOMPtr<nsIPresShell> shell;
+  aPresContext.GetShell(getter_AddRefs(shell));
+  
+  nsCOMPtr<nsIReflowCommand> reflowCmd;
+  nsresult rv = NS_NewHTMLReflowCommand(getter_AddRefs(reflowCmd), this,
+                                        nsIReflowCommand::StyleChanged);
+  if (NS_SUCCEEDED(rv)) 
+    shell->AppendReflowCommand(reflowCmd);
+    */
 }
 
+
+
 nsIFrame*
 nsGrippyFrame::GetChildBeforeAfter(nsIFrame* start, PRBool before)
 {
diff --git a/layout/xul/base/src/nsGrippyFrame.h b/layout/xul/base/src/nsGrippyFrame.h
index db0a524c0c6..dfcd12db018 100644
--- a/layout/xul/base/src/nsGrippyFrame.h
+++ b/layout/xul/base/src/nsGrippyFrame.h
@@ -44,15 +44,17 @@ public:
   static nsIFrame* GetChildAt(nsIFrame* parent, PRInt32 index);
   static PRInt32 IndexOf(nsIFrame* parent, nsIFrame* child);
   static PRInt32 CountFrames(nsIFrame* aFrame);
-  nsGrippyFrame();
+  nsGrippyFrame();  
 
 protected:
   virtual void MouseClicked(nsIPresContext& aPresContext);
+
+private:
+
   PRBool mCollapsed;
   nsString mCollapsedChildStyle;
   nsCOMPtr<nsIContent> mCollapsedChild;
-
-  
+  PRBool mDidDrag;
 }; // class nsTabFrame