diff --git a/content/base/src/nsDOMAttribute.cpp b/content/base/src/nsDOMAttribute.cpp
index b14467b7c91b..77795865214e 100644
--- a/content/base/src/nsDOMAttribute.cpp
+++ b/content/base/src/nsDOMAttribute.cpp
@@ -480,10 +480,14 @@ nsDOMAttribute::Clone(nsINodeInfo *aNodeInfo, nsINode **aResult) const
 }
 
 NS_IMETHODIMP
-nsDOMAttribute::CloneNode(bool aDeep, nsIDOMNode** aResult)
+nsDOMAttribute::CloneNode(bool aDeep, PRUint8 aOptionalArgc, nsIDOMNode** aResult)
 {
   OwnerDoc()->WarnOnceAbout(nsIDocument::eCloneNode);
 
+  if (!aOptionalArgc) {
+    aDeep = true;
+  }
+
   return nsNodeUtils::CloneNodeImpl(this, aDeep, true, aResult);
 }
 
diff --git a/content/base/src/nsDocument.cpp b/content/base/src/nsDocument.cpp
index dbf7d9d85466..486a7b514585 100644
--- a/content/base/src/nsDocument.cpp
+++ b/content/base/src/nsDocument.cpp
@@ -5830,8 +5830,12 @@ nsDocument::AppendChild(nsIDOMNode* aNewChild, nsIDOMNode** aReturn)
 }
 
 NS_IMETHODIMP
-nsDocument::CloneNode(bool aDeep, nsIDOMNode** aReturn)
+nsDocument::CloneNode(bool aDeep, PRUint8 aOptionalArgc, nsIDOMNode** aReturn)
 {
+  if (!aOptionalArgc) {
+    aDeep = true;
+  }
+  
   return nsNodeUtils::CloneNodeImpl(this, aDeep, !mCreatingStaticClone, aReturn);
 }
 
@@ -8062,7 +8066,7 @@ nsIDocument::CreateStaticClone(nsISupports* aCloneContainer)
   nsCOMPtr<nsISupports> originalContainer = GetContainer();
   SetContainer(aCloneContainer);
   nsCOMPtr<nsIDOMNode> clonedNode;
-  nsresult rv = domDoc->CloneNode(true, getter_AddRefs(clonedNode));
+  nsresult rv = domDoc->CloneNode(true, 1, getter_AddRefs(clonedNode));
   SetContainer(originalContainer);
 
   nsCOMPtr<nsIDocument> clonedDoc;
diff --git a/content/base/src/nsGenericDOMDataNode.h b/content/base/src/nsGenericDOMDataNode.h
index 2d87862ee343..4540987c8cfc 100644
--- a/content/base/src/nsGenericDOMDataNode.h
+++ b/content/base/src/nsGenericDOMDataNode.h
@@ -143,8 +143,12 @@ public:
   nsresult IsSupported(const nsAString& aFeature,
                        const nsAString& aVersion,
                        bool* aReturn);
-  nsresult CloneNode(bool aDeep, nsIDOMNode** aReturn)
+  nsresult CloneNode(bool aDeep, PRUint8 aOptionalArgc, nsIDOMNode** aReturn)
   {
+    if (!aOptionalArgc) {
+      aDeep = true;
+    }
+    
     return nsNodeUtils::CloneNodeImpl(this, aDeep, true, aReturn);
   }
 
diff --git a/content/base/src/nsGenericElement.h b/content/base/src/nsGenericElement.h
index 1417a46ce64b..bf2b1f418513 100644
--- a/content/base/src/nsGenericElement.h
+++ b/content/base/src/nsGenericElement.h
@@ -437,8 +437,12 @@ public:
   // nsIDOMElement method implementation
   NS_DECL_NSIDOMELEMENT
 
-  nsresult CloneNode(bool aDeep, nsIDOMNode **aResult)
+  nsresult CloneNode(bool aDeep, PRUint8 aOptionalArgc, nsIDOMNode **aResult)
   {
+    if (!aOptionalArgc) {
+      aDeep = true;
+    }
+    
     return nsNodeUtils::CloneNodeImpl(this, aDeep, true, aResult);
   }
 
diff --git a/content/base/src/nsRange.cpp b/content/base/src/nsRange.cpp
index 01d86583e4f4..b299053e5e64 100644
--- a/content/base/src/nsRange.cpp
+++ b/content/base/src/nsRange.cpp
@@ -1596,7 +1596,7 @@ nsresult nsRange::CutContents(nsIDOMDocumentFragment** aFragment)
                                            cutValue);
               NS_ENSURE_SUCCESS(rv, rv);
               nsCOMPtr<nsIDOMNode> clone;
-              rv = charData->CloneNode(false, getter_AddRefs(clone));
+              rv = charData->CloneNode(false, 1, getter_AddRefs(clone));
               NS_ENSURE_SUCCESS(rv, rv);
               clone->SetNodeValue(cutValue);
               nodeToResult = clone;
@@ -1656,7 +1656,7 @@ nsresult nsRange::CutContents(nsIDOMDocumentFragment** aFragment)
       {
         if (retval) {
           nsCOMPtr<nsIDOMNode> clone;
-          rv = node->CloneNode(false, getter_AddRefs(clone));
+          rv = node->CloneNode(false, 1, getter_AddRefs(clone));
           NS_ENSURE_SUCCESS(rv, rv);
           nodeToResult = clone;
         }
@@ -1827,7 +1827,7 @@ nsRange::CloneParentsBetween(nsIDOMNode *aAncestor,
   {
     nsCOMPtr<nsIDOMNode> clone, tmpNode;
 
-    res = parent->CloneNode(false, getter_AddRefs(clone));
+    res = parent->CloneNode(false, 1, getter_AddRefs(clone));
 
     if (NS_FAILED(res)) return res;
     if (!clone)         return NS_ERROR_FAILURE;
@@ -1928,7 +1928,7 @@ nsRange::CloneContents(nsIDOMDocumentFragment** aReturn)
     // Clone the current subtree!
 
     nsCOMPtr<nsIDOMNode> clone;
-    res = node->CloneNode(deepClone, getter_AddRefs(clone));
+    res = node->CloneNode(deepClone, 1, getter_AddRefs(clone));
     if (NS_FAILED(res)) return res;
 
     // If it's CharacterData, make sure we only clone what
diff --git a/content/base/test/Makefile.in b/content/base/test/Makefile.in
index e6edf80b0385..5cbfadf1bf77 100644
--- a/content/base/test/Makefile.in
+++ b/content/base/test/Makefile.in
@@ -555,6 +555,7 @@ _TEST_FILES2 = \
 		file_bug717511_2.html \
 		file_bug717511_2.html^headers^ \
 		test_bug726364.html \
+		test_bug698381.html \
 		$(NULL)
 
 _CHROME_FILES =	\
diff --git a/content/base/test/test_bug698381.html b/content/base/test/test_bug698381.html
new file mode 100644
index 000000000000..2acc82eaf514
--- /dev/null
+++ b/content/base/test/test_bug698381.html
@@ -0,0 +1,56 @@
+<!DOCTYPE HTML>
+<html>
+  <!--
+    https://bugzilla.mozilla.org/show_bug.cgi?id=698381
+  -->
+  <head>
+    <title>Test for Bug 698381</title>
+    <script type="text/javascript"
+      src="/tests/SimpleTest/SimpleTest.js"></script>
+    <script src="/tests/SimpleTest/EventUtils.js"
+      type="text/javascript"></script>
+    <link rel="stylesheet" type="text/css"
+      href="/tests/SimpleTest/test.css" />
+  </head>
+  <body onload="runTests();">
+    <a target="_blank"
+      href="https://bugzilla.mozilla.org/show_bug.cgi?id=698381">
+      Mozilla Bug 698381</a>
+    <p id="display"></p>
+    <div id="content" style="display: none"></div>
+    <div id="noChildren" style="display: none"></div>
+    <div id="hasChildren" style="display: none">
+      <div id="childOne" style="display: none"></div>
+    </div>
+    <pre id="test">
+      <script type="text/javascript">
+        /*
+          Checks to see if default parameter handling is correct when 0
+          parameters are passed.
+
+          If none are passed, then Node.cloneNode should default aDeep
+          to true.
+        */
+        SimpleTest.waitForExplicitFinish();
+
+        var hasChildren = document.getElementById("hasChildren"),
+            noChildren = document.getElementById("noChildren"),
+            clonedNode;
+
+        function runTests() {
+
+          // Test Node.cloneNode when no arguments are given
+          clonedNode = hasChildren.cloneNode();
+          is(clonedNode.hasChildNodes(), true, "Node.cloneNode with true " +
+            "default on a node with children clones the child nodes.");
+
+          clonedNode = noChildren.cloneNode();
+          is(clonedNode.hasChildNodes(), false, "Node.cloneNode with true " +
+            "default on a node without children doesn't clone child nodes." );
+
+          SimpleTest.finish();
+        }
+      </script>
+    </pre>
+  </body>
+</html>
diff --git a/content/html/content/src/nsHTMLSelectElement.cpp b/content/html/content/src/nsHTMLSelectElement.cpp
index 288edd877e94..a7112056b669 100644
--- a/content/html/content/src/nsHTMLSelectElement.cpp
+++ b/content/html/content/src/nsHTMLSelectElement.cpp
@@ -808,7 +808,7 @@ nsHTMLSelectElement::SetLength(PRUint32 aLength)
       if (i + 1 < aLength) {
         nsCOMPtr<nsIDOMNode> newNode;
 
-        rv = node->CloneNode(true, getter_AddRefs(newNode));
+        rv = node->CloneNode(true, 1, getter_AddRefs(newNode));
         NS_ENSURE_SUCCESS(rv, rv);
 
         node = newNode;
diff --git a/content/xslt/src/xpath/nsXPathNamespace.cpp b/content/xslt/src/xpath/nsXPathNamespace.cpp
index 15560515dd42..b977d4590e02 100644
--- a/content/xslt/src/xpath/nsXPathNamespace.cpp
+++ b/content/xslt/src/xpath/nsXPathNamespace.cpp
@@ -153,7 +153,7 @@ NS_IMETHODIMP nsXPathNamespace::HasChildNodes(bool *aResult)
 }
 
 /* nsIDOMNode cloneNode (in boolean deep); */
-NS_IMETHODIMP nsXPathNamespace::CloneNode(bool deep, nsIDOMNode **aResult)
+NS_IMETHODIMP nsXPathNamespace::CloneNode(bool deep, PRUint8 aOptionalArgc, nsIDOMNode **aResult)
 {
     return NS_ERROR_NOT_IMPLEMENTED;
 }
diff --git a/content/xul/templates/src/nsXULContentBuilder.cpp b/content/xul/templates/src/nsXULContentBuilder.cpp
index d158b50e5a44..8006fec2f2e2 100644
--- a/content/xul/templates/src/nsXULContentBuilder.cpp
+++ b/content/xul/templates/src/nsXULContentBuilder.cpp
@@ -677,7 +677,7 @@ nsXULContentBuilder::BuildContentFromTemplate(nsIContent *aTemplateNode,
                 return NS_ERROR_FAILURE;
             }
             nsCOMPtr<nsIDOMNode> clonedNode;
-            tmplTextNode->CloneNode(false, getter_AddRefs(clonedNode));
+            tmplTextNode->CloneNode(false, 1, getter_AddRefs(clonedNode));
             nsCOMPtr<nsIContent> clonedContent = do_QueryInterface(clonedNode);
             if (!clonedContent) {
                 NS_ERROR("failed to clone textnode");
diff --git a/dom/interfaces/core/nsIDOMNode.idl b/dom/interfaces/core/nsIDOMNode.idl
index 7456fadabd50..fe45006791bd 100644
--- a/dom/interfaces/core/nsIDOMNode.idl
+++ b/dom/interfaces/core/nsIDOMNode.idl
@@ -52,7 +52,7 @@ interface nsIDOMUserDataHandler;
  * http://dvcs.w3.org/hg/domcore/raw-file/tip/Overview.html
  */
 
-[scriptable, uuid(ce82fb71-60f2-4c38-be31-de5f2f90dada)]
+[scriptable, uuid(5e9bcec9-5928-4f77-8a9c-424ef01c20e1)]
 interface nsIDOMNode : nsISupports
 {
   const unsigned short      ELEMENT_NODE       = 1;
@@ -94,7 +94,8 @@ interface nsIDOMNode : nsISupports
   nsIDOMNode                appendChild(in nsIDOMNode newChild)
                                          raises(DOMException);
   boolean                   hasChildNodes();
-  nsIDOMNode                cloneNode(in boolean deep);
+  // Modified in DOM Level 4:
+  [optional_argc] nsIDOMNode                cloneNode([optional] in boolean deep);
   // Modified in DOM Level 2:
   void                      normalize();
   // Introduced in DOM Level 2:
diff --git a/editor/libeditor/base/SplitElementTxn.cpp b/editor/libeditor/base/SplitElementTxn.cpp
index 29e1f11eb479..ec03d0600a34 100644
--- a/editor/libeditor/base/SplitElementTxn.cpp
+++ b/editor/libeditor/base/SplitElementTxn.cpp
@@ -98,7 +98,7 @@ NS_IMETHODIMP SplitElementTxn::DoTransaction(void)
   if (!mExistingRightNode || !mEditor) { return NS_ERROR_NOT_INITIALIZED; }
 
   // create a new node
-  nsresult result = mExistingRightNode->CloneNode(false, getter_AddRefs(mNewLeftNode));
+  nsresult result = mExistingRightNode->CloneNode(false, 1, getter_AddRefs(mNewLeftNode));
   NS_ASSERTION(((NS_SUCCEEDED(result)) && (mNewLeftNode)), "could not create element.");
   NS_ENSURE_SUCCESS(result, result);
   NS_ENSURE_TRUE(mNewLeftNode, NS_ERROR_NULL_POINTER);
diff --git a/embedding/components/webbrowserpersist/src/nsWebBrowserPersist.cpp b/embedding/components/webbrowserpersist/src/nsWebBrowserPersist.cpp
index 50c33c508794..81af932e100e 100644
--- a/embedding/components/webbrowserpersist/src/nsWebBrowserPersist.cpp
+++ b/embedding/components/webbrowserpersist/src/nsWebBrowserPersist.cpp
@@ -2970,7 +2970,7 @@ nsWebBrowserPersist::GetNodeToFixup(nsIDOMNode *aNodeIn, nsIDOMNode **aNodeOut)
 {
     if (!(mPersistFlags & PERSIST_FLAGS_FIXUP_ORIGINAL_DOM))
     {
-        nsresult rv = aNodeIn->CloneNode(false, aNodeOut);
+        nsresult rv = aNodeIn->CloneNode(false, 1, aNodeOut);
         NS_ENSURE_SUCCESS(rv, rv);
     }
     else