diff --git a/content/base/public/nsIContent.h b/content/base/public/nsIContent.h
index 6368dccf5cbe..1d5fbcd746bb 100644
--- a/content/base/public/nsIContent.h
+++ b/content/base/public/nsIContent.h
@@ -40,6 +40,7 @@ class nsIContent;
 class nsISupportsArray;
 class nsIDOMRange;
 class nsISizeOfHandler;
+class nsINodeInfo;
 
 // IID for the nsIContent interface
 #define NS_ICONTENT_IID       \
@@ -136,6 +137,23 @@ public:
                           const nsString& aValue,
                           PRBool aNotify) = 0;
 
+  /**
+   * Set attribute values. All attribute values are assumed to have a
+   * canonical string representation that can be used for these
+   * methods. The setAttribute method is assumed to perform a translation
+   * of the canonical form into the underlying content specific
+   * form.
+   *
+   * @param aNodeInfo the node info (name, prefix, namespace id) of the
+   * attribute
+   * @param aValue may legitimately be the empty string.
+   *
+   * @param aNotify specifies whether or not the document should be
+   * notified of the attribute change.
+   */
+  NS_IMETHOD SetAttribute(nsINodeInfo* aNodeInfo, const nsString& aValue,
+                          PRBool aNotify) = 0;
+
   /**
    * Get the current value of the attribute. This returns a form that is
    * suitable for passing back into setAttribute.
diff --git a/content/base/src/nsCommentNode.cpp b/content/base/src/nsCommentNode.cpp
index cb7f253795fa..f093d9755cb1 100644
--- a/content/base/src/nsCommentNode.cpp
+++ b/content/base/src/nsCommentNode.cpp
@@ -124,6 +124,10 @@ public:
                           const nsString& aValue, PRBool aNotify) {
     return mInner.SetAttribute(aNameSpaceID, aAttribute, aValue, aNotify);
   }
+  NS_IMETHOD SetAttribute(nsINodeInfo* aNodeInfo,
+                          const nsString& aValue, PRBool aNotify) {
+    return mInner.SetAttribute(aNodeInfo, aValue, aNotify);
+  }
   NS_IMETHOD UnsetAttribute(PRInt32 aNameSpaceID, nsIAtom* aAttribute,
                             PRBool aNotify) {
     return mInner.UnsetAttribute(aNameSpaceID, aAttribute, aNotify);
diff --git a/content/base/src/nsDocumentFragment.cpp b/content/base/src/nsDocumentFragment.cpp
index 95af3f91eab0..b9c3a0721dab 100644
--- a/content/base/src/nsDocumentFragment.cpp
+++ b/content/base/src/nsDocumentFragment.cpp
@@ -164,6 +164,10 @@ public:
                           const nsString& aValue,
                           PRBool aNotify)
     { return NS_OK; }
+  NS_IMETHOD SetAttribute(nsINodeInfo* aNodeInfo,
+                          const nsString& aValue,
+                          PRBool aNotify)
+    { return NS_OK; }
   NS_IMETHOD GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, 
                           nsString& aResult) const
     { return NS_CONTENT_ATTR_NOT_THERE; }
diff --git a/content/base/src/nsGenericDOMDataNode.h b/content/base/src/nsGenericDOMDataNode.h
index e8cf56e28c11..90ba96271a48 100644
--- a/content/base/src/nsGenericDOMDataNode.h
+++ b/content/base/src/nsGenericDOMDataNode.h
@@ -173,6 +173,10 @@ struct nsGenericDOMDataNode {
                         PRBool aNotify) {
     return NS_OK;
   }
+  nsresult SetAttribute(nsINodeInfo *aNodeInfo, const nsString& aValue,
+                        PRBool aNotify) {
+    return NS_OK;
+  }
   nsresult UnsetAttribute(PRInt32 aNameSpaceID, nsIAtom* aAttribute, PRBool aNotify) {
     return NS_OK;
   }
@@ -490,6 +494,10 @@ struct nsGenericDOMDataNode {
                           const nsString& aValue, PRBool aNotify) {        \
     return _g.SetAttribute(aNameSpaceID, aAttribute, aValue, aNotify);     \
   }                                                                        \
+  NS_IMETHOD SetAttribute(nsINodeInfo* aNodeInfo,                          \
+                          const nsString& aValue, PRBool aNotify) {        \
+    return _g.SetAttribute(aNodeInfo, aValue, aNotify);                    \
+  }                                                                        \
   NS_IMETHOD UnsetAttribute(PRInt32 aNameSpaceID, nsIAtom* aAttribute,     \
                             PRBool aNotify) {                              \
     return _g.UnsetAttribute(aNameSpaceID, aAttribute, aNotify);           \
diff --git a/content/base/src/nsGenericElement.cpp b/content/base/src/nsGenericElement.cpp
index 9e6155549a29..d9448a02847e 100644
--- a/content/base/src/nsGenericElement.cpp
+++ b/content/base/src/nsGenericElement.cpp
@@ -2300,6 +2300,24 @@ nsGenericContainerElement::SetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,
   return rv;
 }
 
+nsresult 
+nsGenericContainerElement::SetAttribute(nsINodeInfo* aNodeInfo, 
+                                        const nsString& aValue,
+                                        PRBool aNotify)
+{
+  NS_ENSURE_ARG_POINTER(aNodeInfo);
+
+  nsCOMPtr<nsIAtom> atom;
+  PRInt32 nsid;
+
+  aNodeInfo->GetNameAtom(*getter_AddRefs(atom));
+  aNodeInfo->GetNamespaceID(nsid);
+
+  // We still rely on the old way of setting the attribute.
+
+  return SetAttribute(nsid, atom, aValue, aNotify);
+}
+
 nsresult 
 nsGenericContainerElement::GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, 
                                         nsString& aResult) const
diff --git a/content/base/src/nsGenericElement.h b/content/base/src/nsGenericElement.h
index a3fdd383e36f..5375784c40b6 100644
--- a/content/base/src/nsGenericElement.h
+++ b/content/base/src/nsGenericElement.h
@@ -312,6 +312,8 @@ public:
   nsresult SetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, 
                         const nsString& aValue,
                         PRBool aNotify);
+  nsresult SetAttribute(nsINodeInfo* aNodeInfo, const nsString& aValue,
+                        PRBool aNotify);
   nsresult GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, 
                         nsString& aResult) const;
   nsresult UnsetAttribute(PRInt32 aNameSpaceID, nsIAtom* aAttribute, 
@@ -555,6 +557,10 @@ public:
                           const nsString& aValue, PRBool aNotify) {        \
     return _g.SetAttribute(aNameSpaceID, aName, aValue, aNotify);          \
   }                                                                        \
+  NS_IMETHOD SetAttribute(nsINodeInfo* aNodeInfo,                          \
+                          const nsString& aValue, PRBool aNotify) {        \
+    return _g.SetAttribute(aNodeInfo, aValue, aNotify);                    \
+  }                                                                        \
   NS_IMETHOD GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,            \
                           nsString& aResult) const {                       \
     return _g.GetAttribute(aNameSpaceID, aName, aResult);                  \
@@ -670,6 +676,10 @@ public:
                           const nsString& aValue, PRBool aNotify) {        \
     return _g.SetAttribute(aNameSpaceID, aName, aValue, aNotify);          \
   }                                                                        \
+  NS_IMETHOD SetAttribute(nsINodeInfo* aNodeInfo,                          \
+                          const nsString& aValue, PRBool aNotify) {        \
+    return _g.SetAttribute(aNodeInfo, aValue, aNotify);                    \
+  }                                                                        \
   NS_IMETHOD GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,            \
                           nsString& aResult) const {                       \
     return _g.GetAttribute(aNameSpaceID, aName, aResult);                  \
@@ -785,6 +795,10 @@ public:
                           const nsString& aValue, PRBool aNotify) {        \
     return _g.SetAttribute(aNameSpaceID, aName, aValue, aNotify);          \
   }                                                                        \
+  NS_IMETHOD SetAttribute(nsINodeInfo* aNodeInfo,                          \
+                          const nsString& aValue, PRBool aNotify) {        \
+    return _g.SetAttribute(aNodeInfo, aValue, aNotify);                    \
+  }                                                                        \
   NS_IMETHOD GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,            \
                           nsString& aResult) const {                       \
     return _g.GetAttribute(aNameSpaceID, aName, aResult);                  \
@@ -898,6 +912,10 @@ public:
                           const nsString& aValue, PRBool aNotify) {        \
     return _g.SetAttribute(aNameSpaceID, aName, aValue, aNotify);          \
   }                                                                        \
+  NS_IMETHOD SetAttribute(nsINodeInfo* aNodeInfo,                          \
+                          const nsString& aValue, PRBool aNotify) {        \
+    return _g.SetAttribute(aNodeInfo, aValue, aNotify);                    \
+  }                                                                        \
   NS_IMETHOD GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,            \
                           nsString& aResult) const {                       \
     return _g.GetAttribute(aNameSpaceID, aName, aResult);                  \
@@ -1015,6 +1033,10 @@ public:
                           const nsString& aValue, PRBool aNotify) {        \
     return _g.SetAttribute(aNameSpaceID, aName, aValue, aNotify);          \
   }                                                                        \
+  NS_IMETHOD SetAttribute(nsINodeInfo* aNodeInfo,                          \
+                          const nsString& aValue, PRBool aNotify) {        \
+    return _g.SetAttribute(aNodeInfo, aValue, aNotify);                    \
+  }                                                                        \
   NS_IMETHOD GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,            \
                           nsString& aResult) const {                       \
     return _g.GetAttribute(aNameSpaceID, aName, aResult);                  \
@@ -1124,6 +1146,10 @@ public:
                           const nsString& aValue, PRBool aNotify) {        \
     return _g.SetAttribute(aNameSpaceID, aName, aValue, aNotify);          \
   }                                                                        \
+  NS_IMETHOD SetAttribute(nsINodeInfo* aNodeInfo,                          \
+                          const nsString& aValue, PRBool aNotify) {        \
+    return _g.SetAttribute(aNodeInfo, aValue, aNotify);                    \
+  }                                                                        \
   NS_IMETHOD GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,            \
                           nsString& aResult) const {                       \
     return _g.GetAttribute(aNameSpaceID, aName, aResult);                  \
diff --git a/content/html/content/src/nsAttributeContent.cpp b/content/html/content/src/nsAttributeContent.cpp
index 961eee0ff679..e24d989c58dc 100644
--- a/content/html/content/src/nsAttributeContent.cpp
+++ b/content/html/content/src/nsAttributeContent.cpp
@@ -127,6 +127,8 @@ public:
 
   NS_IMETHOD SetAttribute(PRInt32 aNameSpaceID, nsIAtom* aAttribute, const nsString& aValue,
                           PRBool aNotify) {  return NS_OK; }
+  NS_IMETHOD SetAttribute(nsINodeInfo *aNodeInfo, const nsString& aValue,
+                          PRBool aNotify) {  return NS_OK; }
   NS_IMETHOD UnsetAttribute(PRInt32 aNameSpaceID, nsIAtom* aAttribute, PRBool aNotify) { return NS_OK; }
   NS_IMETHOD GetAttribute(PRInt32 aNameSpaceID, nsIAtom *aAttribute, nsString &aResult) const {return NS_CONTENT_ATTR_NOT_THERE; }
   NS_IMETHOD GetAttributeNameAt(PRInt32 aIndex, PRInt32& aNameSpaceID, nsIAtom*& aName) const {
diff --git a/content/html/content/src/nsGenericHTMLElement.cpp b/content/html/content/src/nsGenericHTMLElement.cpp
index 2fb9eda92029..117c1cbdc098 100644
--- a/content/html/content/src/nsGenericHTMLElement.cpp
+++ b/content/html/content/src/nsGenericHTMLElement.cpp
@@ -1304,6 +1304,24 @@ nsGenericHTMLElement::SetAttribute(PRInt32 aNameSpaceID,
   return result;
 }
 
+nsresult
+nsGenericHTMLElement::SetAttribute(nsINodeInfo* aNodeInfo,
+                                   const nsString& aValue,
+                                   PRBool aNotify)
+{
+  NS_ENSURE_ARG_POINTER(aNodeInfo);
+
+  nsCOMPtr<nsIAtom> atom;
+  PRInt32 nsid;
+
+  aNodeInfo->GetNameAtom(*getter_AddRefs(atom));
+  aNodeInfo->GetNamespaceID(nsid);
+
+  // We still rely on the old way of setting the attribute.
+
+  return SetAttribute(nsid, atom, aValue, aNotify);
+}
+
 static PRInt32 GetStyleImpactFrom(const nsHTMLValue& aValue)
 {
   PRInt32 hint = NS_STYLE_HINT_NONE;
@@ -3414,6 +3432,24 @@ nsGenericHTMLContainerFormElement::SetAttribute(PRInt32 aNameSpaceID, nsIAtom* a
   return nsGenericHTMLElement::SetAttribute(aNameSpaceID, aName, aValue, aNotify);
 }
 
+nsresult
+nsGenericHTMLContainerFormElement::SetAttribute(nsINodeInfo* aNodeInfo,
+                                                const nsString& aValue,
+                                                PRBool aNotify)
+{
+  NS_ENSURE_ARG_POINTER(aNodeInfo);
+
+  nsCOMPtr<nsIAtom> atom;
+  PRInt32 nsid;
+
+  aNodeInfo->GetNameAtom(*getter_AddRefs(atom));
+  aNodeInfo->GetNamespaceID(nsid);
+
+  // We still rely on the old way of setting the attribute.
+
+  return SetAttribute(nsid, atom, aValue, aNotify);
+}
+
 //----------------------------------------------------------------------
 
 nsGenericHTMLLeafFormElement::nsGenericHTMLLeafFormElement()
@@ -3446,4 +3482,22 @@ nsGenericHTMLLeafFormElement::SetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,
   return nsGenericHTMLElement::SetAttribute(aNameSpaceID, aName, aValue, aNotify);
 }
 
+nsresult
+nsGenericHTMLLeafFormElement::SetAttribute(nsINodeInfo* aNodeInfo,
+                                           const nsString& aValue,
+                                           PRBool aNotify)
+{
+  NS_ENSURE_ARG_POINTER(aNodeInfo);
+
+  nsCOMPtr<nsIAtom> atom;
+  PRInt32 nsid;
+
+  aNodeInfo->GetNameAtom(*getter_AddRefs(atom));
+  aNodeInfo->GetNamespaceID(nsid);
+
+  // We still rely on the old way of setting the attribute.
+
+  return SetAttribute(nsid, atom, aValue, aNotify);
+}
+
 //----------------------------------------------------------------------
diff --git a/content/html/content/src/nsGenericHTMLElement.h b/content/html/content/src/nsGenericHTMLElement.h
index 90410af7a698..241f64e81f21 100644
--- a/content/html/content/src/nsGenericHTMLElement.h
+++ b/content/html/content/src/nsGenericHTMLElement.h
@@ -104,6 +104,7 @@ public:
                             nsIAtom* aOffsetParentTag,
                             nsIContent** aOffsetParent);
 
+
   // Implementation for nsIContent
   nsresult GetNameSpaceID(PRInt32& aNameSpaceID) const;
   nsresult SetDocument(nsIDocument* aDocument, PRBool aDeep);
@@ -114,6 +115,8 @@ public:
                                     nsIAtom*& aPrefix);
   nsresult SetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, const nsString& aValue,
                         PRBool aNotify);
+  nsresult SetAttribute(nsINodeInfo* aNodeInfo, const nsString& aValue,
+                        PRBool aNotify);
   nsresult GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, nsString& aResult) const;
   nsresult UnsetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, PRBool aNotify);
   nsresult GetAttributeNameAt(PRInt32 aIndex,
@@ -460,6 +463,8 @@ public:
   nsresult SetForm(nsIForm* aForm);
   nsresult SetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, const nsString& aValue,
                           PRBool aNotify);
+  nsresult SetAttribute(nsINodeInfo* aNodeInfo, const nsString& aValue,
+                          PRBool aNotify);
   nsresult SetAttribute(const nsString& aName, const nsString& aValue)
   {
     return nsGenericHTMLElement::SetAttribute(aName, aValue);
@@ -478,6 +483,8 @@ public:
   nsresult SetForm(nsIForm* aForm);
   nsresult SetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, const nsString& aValue,
                           PRBool aNotify);
+  nsresult SetAttribute(nsINodeInfo* aNodeInfo, const nsString& aValue,
+                          PRBool aNotify);
   nsresult SetAttribute(const nsString& aName, const nsString& aValue)
   {
     return nsGenericHTMLElement::SetAttribute(aName, aValue);
diff --git a/content/html/content/src/nsHTMLMapElement.cpp b/content/html/content/src/nsHTMLMapElement.cpp
index 6bc653f3426f..08fd0b3570c4 100644
--- a/content/html/content/src/nsHTMLMapElement.cpp
+++ b/content/html/content/src/nsHTMLMapElement.cpp
@@ -125,6 +125,10 @@ public:
                           const nsString& aValue, PRBool aNotify) {        
     return mInner.SetAttribute(aNameSpaceID, aName, aValue, aNotify);          
   }                                                                        
+  NS_IMETHOD SetAttribute(nsINodeInfo* aNodeInfo,
+                          const nsString& aValue, PRBool aNotify) {
+    return mInner.SetAttribute(aNodeInfo, aValue, aNotify);
+  }
   NS_IMETHOD GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,            
                           nsString& aResult) const {                       
     return mInner.GetAttribute(aNameSpaceID, aName, aResult);                  
diff --git a/content/html/content/src/nsHTMLUnknownElement.cpp b/content/html/content/src/nsHTMLUnknownElement.cpp
index 7946d1c99247..2a9da8b90bca 100644
--- a/content/html/content/src/nsHTMLUnknownElement.cpp
+++ b/content/html/content/src/nsHTMLUnknownElement.cpp
@@ -122,6 +122,8 @@ public:
   }
   NS_IMETHOD SetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,
                           const nsString& aValue, PRBool aNotify);
+  NS_IMETHOD SetAttribute(nsINodeInfo* aNodeInfo,
+                          const nsString& aValue, PRBool aNotify);
   NS_IMETHOD GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,
                           nsString& aResult) const {
     return mInner.GetAttribute(aNameSpaceID, aName, aResult);
@@ -426,6 +428,24 @@ nsHTMLUnknownElement::SetAttribute(PRInt32 aNameSpaceID,
   return result;
 }
 
+NS_IMETHODIMP
+nsHTMLUnknownElement::SetAttribute(nsINodeInfo *aNodeInfo,
+                                   const nsString& aValue,
+                                   PRBool aNotify)
+{
+  NS_ENSURE_ARG_POINTER(aNodeInfo);  
+
+  nsCOMPtr<nsIAtom> atom;  
+  PRInt32 nsid;  
+
+  aNodeInfo->GetNameAtom(*getter_AddRefs(atom));  
+  aNodeInfo->GetNamespaceID(nsid);  
+
+  // We still rely on the old way of setting the attribute.  
+  
+  return SetAttribute(nsid, atom, aValue, aNotify);  
+}
+
 NS_IMETHODIMP
 nsHTMLUnknownElement::HandleDOMEvent(nsIPresContext* aPresContext,
                                      nsEvent* aEvent,
diff --git a/content/xml/content/src/nsXMLElement.cpp b/content/xml/content/src/nsXMLElement.cpp
index 83bb19ad5ef1..b590c3ac1986 100644
--- a/content/xml/content/src/nsXMLElement.cpp
+++ b/content/xml/content/src/nsXMLElement.cpp
@@ -216,8 +216,8 @@ nsXMLElement::GetXMLBaseURI(nsIURI **aURI)
 
 NS_IMETHODIMP 
 nsXMLElement::SetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, 
-			                     const nsString& aValue,
-			                     PRBool aNotify)
+                           const nsString& aValue,
+                           PRBool aNotify)
 {
   if ((kNameSpaceID_XLink == aNameSpaceID) &&
       (kTypeAtom == aName)) { 
@@ -240,6 +240,23 @@ nsXMLElement::SetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,
   return mInner.SetAttribute(aNameSpaceID, aName, aValue, aNotify);
 }
 
+NS_IMETHODIMP 
+nsXMLElement::SetAttribute(nsINodeInfo *aNodeInfo, const nsString& aValue,
+                           PRBool aNotify)
+{
+  NS_ENSURE_ARG_POINTER(aNodeInfo);
+
+  nsCOMPtr<nsIAtom> atom;
+  PRInt32 nsid;
+
+  aNodeInfo->GetNameAtom(*getter_AddRefs(atom));
+  aNodeInfo->GetNamespaceID(nsid);
+
+  // We still rely on the old way of setting the attribute.
+
+  return SetAttribute(nsid, atom, aValue, aNotify);
+}
+
 static nsresult WebShellToPresContext(nsIWebShell *aShell, nsIPresContext **aPresContext)
 {
   *aPresContext = nsnull;
diff --git a/content/xml/content/src/nsXMLElement.h b/content/xml/content/src/nsXMLElement.h
index a9621de76ba4..f68bc8455435 100644
--- a/content/xml/content/src/nsXMLElement.h
+++ b/content/xml/content/src/nsXMLElement.h
@@ -118,6 +118,8 @@ public:
   }
   NS_IMETHOD SetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, const nsString& aValue,
                           PRBool aNotify);
+  NS_IMETHOD SetAttribute(nsINodeInfo *aNodeInfo, const nsString& aValue,
+                          PRBool aNotify);
   NS_IMETHOD GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,
                           nsString& aResult) const {
     return mInner.GetAttribute(aNameSpaceID, aName, aResult);
diff --git a/content/xul/content/src/nsXULElement.cpp b/content/xul/content/src/nsXULElement.cpp
index 5d6b1ee6df34..71cf8ca0ca99 100644
--- a/content/xul/content/src/nsXULElement.cpp
+++ b/content/xul/content/src/nsXULElement.cpp
@@ -2867,6 +2867,24 @@ nsXULElement::SetAttribute(PRInt32 aNameSpaceID,
     return rv;
 }
 
+NS_IMETHODIMP 
+nsXULElement::SetAttribute(nsINodeInfo* aNodeInfo, 
+                           const nsString& aValue,
+                           PRBool aNotify)
+{
+  NS_ENSURE_ARG_POINTER(aNodeInfo);
+
+  nsCOMPtr<nsIAtom> atom;
+  PRInt32 nsid;
+
+  aNodeInfo->GetNameAtom(*getter_AddRefs(atom));
+  aNodeInfo->GetNamespaceID(nsid);
+
+  // We still rely on the old way of setting the attribute.
+
+  return SetAttribute(nsid, atom, aValue, aNotify);
+}
+
 NS_IMETHODIMP
 nsXULElement::GetAttribute(PRInt32 aNameSpaceID,
                            nsIAtom* aName,
diff --git a/content/xul/content/src/nsXULElement.h b/content/xul/content/src/nsXULElement.h
index 994bcdd0be09..345dda43ffbf 100644
--- a/content/xul/content/src/nsXULElement.h
+++ b/content/xul/content/src/nsXULElement.h
@@ -395,6 +395,7 @@ public:
     NS_IMETHOD ParseAttributeString(const nsString& aStr, nsIAtom*& aName, PRInt32& aNameSpaceID);
     NS_IMETHOD GetNameSpacePrefixFromId(PRInt32 aNameSpaceID, nsIAtom*& aPrefix);
     NS_IMETHOD SetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, const nsString& aValue, PRBool aNotify);
+    NS_IMETHOD SetAttribute(nsINodeInfo *aNodeInfo, const nsString& aValue, PRBool aNotify);
     NS_IMETHOD GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, nsString& aResult) const;
     NS_IMETHOD UnsetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, PRBool aNotify);
     NS_IMETHOD GetAttributeNameAt(PRInt32 aIndex, PRInt32& aNameSpaceID, 
diff --git a/layout/base/public/nsIContent.h b/layout/base/public/nsIContent.h
index 6368dccf5cbe..1d5fbcd746bb 100644
--- a/layout/base/public/nsIContent.h
+++ b/layout/base/public/nsIContent.h
@@ -40,6 +40,7 @@ class nsIContent;
 class nsISupportsArray;
 class nsIDOMRange;
 class nsISizeOfHandler;
+class nsINodeInfo;
 
 // IID for the nsIContent interface
 #define NS_ICONTENT_IID       \
@@ -136,6 +137,23 @@ public:
                           const nsString& aValue,
                           PRBool aNotify) = 0;
 
+  /**
+   * Set attribute values. All attribute values are assumed to have a
+   * canonical string representation that can be used for these
+   * methods. The setAttribute method is assumed to perform a translation
+   * of the canonical form into the underlying content specific
+   * form.
+   *
+   * @param aNodeInfo the node info (name, prefix, namespace id) of the
+   * attribute
+   * @param aValue may legitimately be the empty string.
+   *
+   * @param aNotify specifies whether or not the document should be
+   * notified of the attribute change.
+   */
+  NS_IMETHOD SetAttribute(nsINodeInfo* aNodeInfo, const nsString& aValue,
+                          PRBool aNotify) = 0;
+
   /**
    * Get the current value of the attribute. This returns a form that is
    * suitable for passing back into setAttribute.
diff --git a/layout/base/src/nsCommentNode.cpp b/layout/base/src/nsCommentNode.cpp
index cb7f253795fa..f093d9755cb1 100644
--- a/layout/base/src/nsCommentNode.cpp
+++ b/layout/base/src/nsCommentNode.cpp
@@ -124,6 +124,10 @@ public:
                           const nsString& aValue, PRBool aNotify) {
     return mInner.SetAttribute(aNameSpaceID, aAttribute, aValue, aNotify);
   }
+  NS_IMETHOD SetAttribute(nsINodeInfo* aNodeInfo,
+                          const nsString& aValue, PRBool aNotify) {
+    return mInner.SetAttribute(aNodeInfo, aValue, aNotify);
+  }
   NS_IMETHOD UnsetAttribute(PRInt32 aNameSpaceID, nsIAtom* aAttribute,
                             PRBool aNotify) {
     return mInner.UnsetAttribute(aNameSpaceID, aAttribute, aNotify);
diff --git a/layout/base/src/nsDocumentFragment.cpp b/layout/base/src/nsDocumentFragment.cpp
index 95af3f91eab0..b9c3a0721dab 100644
--- a/layout/base/src/nsDocumentFragment.cpp
+++ b/layout/base/src/nsDocumentFragment.cpp
@@ -164,6 +164,10 @@ public:
                           const nsString& aValue,
                           PRBool aNotify)
     { return NS_OK; }
+  NS_IMETHOD SetAttribute(nsINodeInfo* aNodeInfo,
+                          const nsString& aValue,
+                          PRBool aNotify)
+    { return NS_OK; }
   NS_IMETHOD GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, 
                           nsString& aResult) const
     { return NS_CONTENT_ATTR_NOT_THERE; }
diff --git a/layout/base/src/nsGenericDOMDataNode.h b/layout/base/src/nsGenericDOMDataNode.h
index e8cf56e28c11..90ba96271a48 100644
--- a/layout/base/src/nsGenericDOMDataNode.h
+++ b/layout/base/src/nsGenericDOMDataNode.h
@@ -173,6 +173,10 @@ struct nsGenericDOMDataNode {
                         PRBool aNotify) {
     return NS_OK;
   }
+  nsresult SetAttribute(nsINodeInfo *aNodeInfo, const nsString& aValue,
+                        PRBool aNotify) {
+    return NS_OK;
+  }
   nsresult UnsetAttribute(PRInt32 aNameSpaceID, nsIAtom* aAttribute, PRBool aNotify) {
     return NS_OK;
   }
@@ -490,6 +494,10 @@ struct nsGenericDOMDataNode {
                           const nsString& aValue, PRBool aNotify) {        \
     return _g.SetAttribute(aNameSpaceID, aAttribute, aValue, aNotify);     \
   }                                                                        \
+  NS_IMETHOD SetAttribute(nsINodeInfo* aNodeInfo,                          \
+                          const nsString& aValue, PRBool aNotify) {        \
+    return _g.SetAttribute(aNodeInfo, aValue, aNotify);                    \
+  }                                                                        \
   NS_IMETHOD UnsetAttribute(PRInt32 aNameSpaceID, nsIAtom* aAttribute,     \
                             PRBool aNotify) {                              \
     return _g.UnsetAttribute(aNameSpaceID, aAttribute, aNotify);           \
diff --git a/layout/base/src/nsGenericElement.cpp b/layout/base/src/nsGenericElement.cpp
index 9e6155549a29..d9448a02847e 100644
--- a/layout/base/src/nsGenericElement.cpp
+++ b/layout/base/src/nsGenericElement.cpp
@@ -2300,6 +2300,24 @@ nsGenericContainerElement::SetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,
   return rv;
 }
 
+nsresult 
+nsGenericContainerElement::SetAttribute(nsINodeInfo* aNodeInfo, 
+                                        const nsString& aValue,
+                                        PRBool aNotify)
+{
+  NS_ENSURE_ARG_POINTER(aNodeInfo);
+
+  nsCOMPtr<nsIAtom> atom;
+  PRInt32 nsid;
+
+  aNodeInfo->GetNameAtom(*getter_AddRefs(atom));
+  aNodeInfo->GetNamespaceID(nsid);
+
+  // We still rely on the old way of setting the attribute.
+
+  return SetAttribute(nsid, atom, aValue, aNotify);
+}
+
 nsresult 
 nsGenericContainerElement::GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, 
                                         nsString& aResult) const
diff --git a/layout/base/src/nsGenericElement.h b/layout/base/src/nsGenericElement.h
index a3fdd383e36f..5375784c40b6 100644
--- a/layout/base/src/nsGenericElement.h
+++ b/layout/base/src/nsGenericElement.h
@@ -312,6 +312,8 @@ public:
   nsresult SetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, 
                         const nsString& aValue,
                         PRBool aNotify);
+  nsresult SetAttribute(nsINodeInfo* aNodeInfo, const nsString& aValue,
+                        PRBool aNotify);
   nsresult GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, 
                         nsString& aResult) const;
   nsresult UnsetAttribute(PRInt32 aNameSpaceID, nsIAtom* aAttribute, 
@@ -555,6 +557,10 @@ public:
                           const nsString& aValue, PRBool aNotify) {        \
     return _g.SetAttribute(aNameSpaceID, aName, aValue, aNotify);          \
   }                                                                        \
+  NS_IMETHOD SetAttribute(nsINodeInfo* aNodeInfo,                          \
+                          const nsString& aValue, PRBool aNotify) {        \
+    return _g.SetAttribute(aNodeInfo, aValue, aNotify);                    \
+  }                                                                        \
   NS_IMETHOD GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,            \
                           nsString& aResult) const {                       \
     return _g.GetAttribute(aNameSpaceID, aName, aResult);                  \
@@ -670,6 +676,10 @@ public:
                           const nsString& aValue, PRBool aNotify) {        \
     return _g.SetAttribute(aNameSpaceID, aName, aValue, aNotify);          \
   }                                                                        \
+  NS_IMETHOD SetAttribute(nsINodeInfo* aNodeInfo,                          \
+                          const nsString& aValue, PRBool aNotify) {        \
+    return _g.SetAttribute(aNodeInfo, aValue, aNotify);                    \
+  }                                                                        \
   NS_IMETHOD GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,            \
                           nsString& aResult) const {                       \
     return _g.GetAttribute(aNameSpaceID, aName, aResult);                  \
@@ -785,6 +795,10 @@ public:
                           const nsString& aValue, PRBool aNotify) {        \
     return _g.SetAttribute(aNameSpaceID, aName, aValue, aNotify);          \
   }                                                                        \
+  NS_IMETHOD SetAttribute(nsINodeInfo* aNodeInfo,                          \
+                          const nsString& aValue, PRBool aNotify) {        \
+    return _g.SetAttribute(aNodeInfo, aValue, aNotify);                    \
+  }                                                                        \
   NS_IMETHOD GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,            \
                           nsString& aResult) const {                       \
     return _g.GetAttribute(aNameSpaceID, aName, aResult);                  \
@@ -898,6 +912,10 @@ public:
                           const nsString& aValue, PRBool aNotify) {        \
     return _g.SetAttribute(aNameSpaceID, aName, aValue, aNotify);          \
   }                                                                        \
+  NS_IMETHOD SetAttribute(nsINodeInfo* aNodeInfo,                          \
+                          const nsString& aValue, PRBool aNotify) {        \
+    return _g.SetAttribute(aNodeInfo, aValue, aNotify);                    \
+  }                                                                        \
   NS_IMETHOD GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,            \
                           nsString& aResult) const {                       \
     return _g.GetAttribute(aNameSpaceID, aName, aResult);                  \
@@ -1015,6 +1033,10 @@ public:
                           const nsString& aValue, PRBool aNotify) {        \
     return _g.SetAttribute(aNameSpaceID, aName, aValue, aNotify);          \
   }                                                                        \
+  NS_IMETHOD SetAttribute(nsINodeInfo* aNodeInfo,                          \
+                          const nsString& aValue, PRBool aNotify) {        \
+    return _g.SetAttribute(aNodeInfo, aValue, aNotify);                    \
+  }                                                                        \
   NS_IMETHOD GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,            \
                           nsString& aResult) const {                       \
     return _g.GetAttribute(aNameSpaceID, aName, aResult);                  \
@@ -1124,6 +1146,10 @@ public:
                           const nsString& aValue, PRBool aNotify) {        \
     return _g.SetAttribute(aNameSpaceID, aName, aValue, aNotify);          \
   }                                                                        \
+  NS_IMETHOD SetAttribute(nsINodeInfo* aNodeInfo,                          \
+                          const nsString& aValue, PRBool aNotify) {        \
+    return _g.SetAttribute(aNodeInfo, aValue, aNotify);                    \
+  }                                                                        \
   NS_IMETHOD GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,            \
                           nsString& aResult) const {                       \
     return _g.GetAttribute(aNameSpaceID, aName, aResult);                  \
diff --git a/layout/html/content/src/nsAttributeContent.cpp b/layout/html/content/src/nsAttributeContent.cpp
index 961eee0ff679..e24d989c58dc 100644
--- a/layout/html/content/src/nsAttributeContent.cpp
+++ b/layout/html/content/src/nsAttributeContent.cpp
@@ -127,6 +127,8 @@ public:
 
   NS_IMETHOD SetAttribute(PRInt32 aNameSpaceID, nsIAtom* aAttribute, const nsString& aValue,
                           PRBool aNotify) {  return NS_OK; }
+  NS_IMETHOD SetAttribute(nsINodeInfo *aNodeInfo, const nsString& aValue,
+                          PRBool aNotify) {  return NS_OK; }
   NS_IMETHOD UnsetAttribute(PRInt32 aNameSpaceID, nsIAtom* aAttribute, PRBool aNotify) { return NS_OK; }
   NS_IMETHOD GetAttribute(PRInt32 aNameSpaceID, nsIAtom *aAttribute, nsString &aResult) const {return NS_CONTENT_ATTR_NOT_THERE; }
   NS_IMETHOD GetAttributeNameAt(PRInt32 aIndex, PRInt32& aNameSpaceID, nsIAtom*& aName) const {
diff --git a/layout/html/content/src/nsGenericHTMLElement.cpp b/layout/html/content/src/nsGenericHTMLElement.cpp
index 2fb9eda92029..117c1cbdc098 100644
--- a/layout/html/content/src/nsGenericHTMLElement.cpp
+++ b/layout/html/content/src/nsGenericHTMLElement.cpp
@@ -1304,6 +1304,24 @@ nsGenericHTMLElement::SetAttribute(PRInt32 aNameSpaceID,
   return result;
 }
 
+nsresult
+nsGenericHTMLElement::SetAttribute(nsINodeInfo* aNodeInfo,
+                                   const nsString& aValue,
+                                   PRBool aNotify)
+{
+  NS_ENSURE_ARG_POINTER(aNodeInfo);
+
+  nsCOMPtr<nsIAtom> atom;
+  PRInt32 nsid;
+
+  aNodeInfo->GetNameAtom(*getter_AddRefs(atom));
+  aNodeInfo->GetNamespaceID(nsid);
+
+  // We still rely on the old way of setting the attribute.
+
+  return SetAttribute(nsid, atom, aValue, aNotify);
+}
+
 static PRInt32 GetStyleImpactFrom(const nsHTMLValue& aValue)
 {
   PRInt32 hint = NS_STYLE_HINT_NONE;
@@ -3414,6 +3432,24 @@ nsGenericHTMLContainerFormElement::SetAttribute(PRInt32 aNameSpaceID, nsIAtom* a
   return nsGenericHTMLElement::SetAttribute(aNameSpaceID, aName, aValue, aNotify);
 }
 
+nsresult
+nsGenericHTMLContainerFormElement::SetAttribute(nsINodeInfo* aNodeInfo,
+                                                const nsString& aValue,
+                                                PRBool aNotify)
+{
+  NS_ENSURE_ARG_POINTER(aNodeInfo);
+
+  nsCOMPtr<nsIAtom> atom;
+  PRInt32 nsid;
+
+  aNodeInfo->GetNameAtom(*getter_AddRefs(atom));
+  aNodeInfo->GetNamespaceID(nsid);
+
+  // We still rely on the old way of setting the attribute.
+
+  return SetAttribute(nsid, atom, aValue, aNotify);
+}
+
 //----------------------------------------------------------------------
 
 nsGenericHTMLLeafFormElement::nsGenericHTMLLeafFormElement()
@@ -3446,4 +3482,22 @@ nsGenericHTMLLeafFormElement::SetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,
   return nsGenericHTMLElement::SetAttribute(aNameSpaceID, aName, aValue, aNotify);
 }
 
+nsresult
+nsGenericHTMLLeafFormElement::SetAttribute(nsINodeInfo* aNodeInfo,
+                                           const nsString& aValue,
+                                           PRBool aNotify)
+{
+  NS_ENSURE_ARG_POINTER(aNodeInfo);
+
+  nsCOMPtr<nsIAtom> atom;
+  PRInt32 nsid;
+
+  aNodeInfo->GetNameAtom(*getter_AddRefs(atom));
+  aNodeInfo->GetNamespaceID(nsid);
+
+  // We still rely on the old way of setting the attribute.
+
+  return SetAttribute(nsid, atom, aValue, aNotify);
+}
+
 //----------------------------------------------------------------------
diff --git a/layout/html/content/src/nsGenericHTMLElement.h b/layout/html/content/src/nsGenericHTMLElement.h
index 90410af7a698..241f64e81f21 100644
--- a/layout/html/content/src/nsGenericHTMLElement.h
+++ b/layout/html/content/src/nsGenericHTMLElement.h
@@ -104,6 +104,7 @@ public:
                             nsIAtom* aOffsetParentTag,
                             nsIContent** aOffsetParent);
 
+
   // Implementation for nsIContent
   nsresult GetNameSpaceID(PRInt32& aNameSpaceID) const;
   nsresult SetDocument(nsIDocument* aDocument, PRBool aDeep);
@@ -114,6 +115,8 @@ public:
                                     nsIAtom*& aPrefix);
   nsresult SetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, const nsString& aValue,
                         PRBool aNotify);
+  nsresult SetAttribute(nsINodeInfo* aNodeInfo, const nsString& aValue,
+                        PRBool aNotify);
   nsresult GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, nsString& aResult) const;
   nsresult UnsetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, PRBool aNotify);
   nsresult GetAttributeNameAt(PRInt32 aIndex,
@@ -460,6 +463,8 @@ public:
   nsresult SetForm(nsIForm* aForm);
   nsresult SetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, const nsString& aValue,
                           PRBool aNotify);
+  nsresult SetAttribute(nsINodeInfo* aNodeInfo, const nsString& aValue,
+                          PRBool aNotify);
   nsresult SetAttribute(const nsString& aName, const nsString& aValue)
   {
     return nsGenericHTMLElement::SetAttribute(aName, aValue);
@@ -478,6 +483,8 @@ public:
   nsresult SetForm(nsIForm* aForm);
   nsresult SetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, const nsString& aValue,
                           PRBool aNotify);
+  nsresult SetAttribute(nsINodeInfo* aNodeInfo, const nsString& aValue,
+                          PRBool aNotify);
   nsresult SetAttribute(const nsString& aName, const nsString& aValue)
   {
     return nsGenericHTMLElement::SetAttribute(aName, aValue);
diff --git a/layout/html/content/src/nsHTMLMapElement.cpp b/layout/html/content/src/nsHTMLMapElement.cpp
index 6bc653f3426f..08fd0b3570c4 100644
--- a/layout/html/content/src/nsHTMLMapElement.cpp
+++ b/layout/html/content/src/nsHTMLMapElement.cpp
@@ -125,6 +125,10 @@ public:
                           const nsString& aValue, PRBool aNotify) {        
     return mInner.SetAttribute(aNameSpaceID, aName, aValue, aNotify);          
   }                                                                        
+  NS_IMETHOD SetAttribute(nsINodeInfo* aNodeInfo,
+                          const nsString& aValue, PRBool aNotify) {
+    return mInner.SetAttribute(aNodeInfo, aValue, aNotify);
+  }
   NS_IMETHOD GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,            
                           nsString& aResult) const {                       
     return mInner.GetAttribute(aNameSpaceID, aName, aResult);                  
diff --git a/layout/html/content/src/nsHTMLUnknownElement.cpp b/layout/html/content/src/nsHTMLUnknownElement.cpp
index 7946d1c99247..2a9da8b90bca 100644
--- a/layout/html/content/src/nsHTMLUnknownElement.cpp
+++ b/layout/html/content/src/nsHTMLUnknownElement.cpp
@@ -122,6 +122,8 @@ public:
   }
   NS_IMETHOD SetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,
                           const nsString& aValue, PRBool aNotify);
+  NS_IMETHOD SetAttribute(nsINodeInfo* aNodeInfo,
+                          const nsString& aValue, PRBool aNotify);
   NS_IMETHOD GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,
                           nsString& aResult) const {
     return mInner.GetAttribute(aNameSpaceID, aName, aResult);
@@ -426,6 +428,24 @@ nsHTMLUnknownElement::SetAttribute(PRInt32 aNameSpaceID,
   return result;
 }
 
+NS_IMETHODIMP
+nsHTMLUnknownElement::SetAttribute(nsINodeInfo *aNodeInfo,
+                                   const nsString& aValue,
+                                   PRBool aNotify)
+{
+  NS_ENSURE_ARG_POINTER(aNodeInfo);  
+
+  nsCOMPtr<nsIAtom> atom;  
+  PRInt32 nsid;  
+
+  aNodeInfo->GetNameAtom(*getter_AddRefs(atom));  
+  aNodeInfo->GetNamespaceID(nsid);  
+
+  // We still rely on the old way of setting the attribute.  
+  
+  return SetAttribute(nsid, atom, aValue, aNotify);  
+}
+
 NS_IMETHODIMP
 nsHTMLUnknownElement::HandleDOMEvent(nsIPresContext* aPresContext,
                                      nsEvent* aEvent,
diff --git a/layout/xml/content/src/nsGenericXMLElement.h b/layout/xml/content/src/nsGenericXMLElement.h
index 0ca315992a80..637c6f3e9bab 100644
--- a/layout/xml/content/src/nsGenericXMLElement.h
+++ b/layout/xml/content/src/nsGenericXMLElement.h
@@ -62,6 +62,12 @@ public:
     return nsGenericContainerElement::SetAttribute(aNameSpaceID, aName,
                                                    aValue, aNotify);
   }
+  nsresult SetAttribute(nsINodeInfo *aNodeInfo,
+                        const nsString& aValue,
+                        PRBool aNotify)
+  {
+    return nsGenericContainerElement::SetAttribute(aNodeInfo, aValue, aNotify);
+  }
   nsresult GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, 
                         nsString& aResult) const
   {
diff --git a/layout/xml/content/src/nsXMLElement.cpp b/layout/xml/content/src/nsXMLElement.cpp
index 83bb19ad5ef1..b590c3ac1986 100644
--- a/layout/xml/content/src/nsXMLElement.cpp
+++ b/layout/xml/content/src/nsXMLElement.cpp
@@ -216,8 +216,8 @@ nsXMLElement::GetXMLBaseURI(nsIURI **aURI)
 
 NS_IMETHODIMP 
 nsXMLElement::SetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, 
-			                     const nsString& aValue,
-			                     PRBool aNotify)
+                           const nsString& aValue,
+                           PRBool aNotify)
 {
   if ((kNameSpaceID_XLink == aNameSpaceID) &&
       (kTypeAtom == aName)) { 
@@ -240,6 +240,23 @@ nsXMLElement::SetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,
   return mInner.SetAttribute(aNameSpaceID, aName, aValue, aNotify);
 }
 
+NS_IMETHODIMP 
+nsXMLElement::SetAttribute(nsINodeInfo *aNodeInfo, const nsString& aValue,
+                           PRBool aNotify)
+{
+  NS_ENSURE_ARG_POINTER(aNodeInfo);
+
+  nsCOMPtr<nsIAtom> atom;
+  PRInt32 nsid;
+
+  aNodeInfo->GetNameAtom(*getter_AddRefs(atom));
+  aNodeInfo->GetNamespaceID(nsid);
+
+  // We still rely on the old way of setting the attribute.
+
+  return SetAttribute(nsid, atom, aValue, aNotify);
+}
+
 static nsresult WebShellToPresContext(nsIWebShell *aShell, nsIPresContext **aPresContext)
 {
   *aPresContext = nsnull;
diff --git a/layout/xml/content/src/nsXMLElement.h b/layout/xml/content/src/nsXMLElement.h
index a9621de76ba4..f68bc8455435 100644
--- a/layout/xml/content/src/nsXMLElement.h
+++ b/layout/xml/content/src/nsXMLElement.h
@@ -118,6 +118,8 @@ public:
   }
   NS_IMETHOD SetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, const nsString& aValue,
                           PRBool aNotify);
+  NS_IMETHOD SetAttribute(nsINodeInfo *aNodeInfo, const nsString& aValue,
+                          PRBool aNotify);
   NS_IMETHOD GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName,
                           nsString& aResult) const {
     return mInner.GetAttribute(aNameSpaceID, aName, aResult);
diff --git a/rdf/content/src/nsXULElement.cpp b/rdf/content/src/nsXULElement.cpp
index 5d6b1ee6df34..71cf8ca0ca99 100644
--- a/rdf/content/src/nsXULElement.cpp
+++ b/rdf/content/src/nsXULElement.cpp
@@ -2867,6 +2867,24 @@ nsXULElement::SetAttribute(PRInt32 aNameSpaceID,
     return rv;
 }
 
+NS_IMETHODIMP 
+nsXULElement::SetAttribute(nsINodeInfo* aNodeInfo, 
+                           const nsString& aValue,
+                           PRBool aNotify)
+{
+  NS_ENSURE_ARG_POINTER(aNodeInfo);
+
+  nsCOMPtr<nsIAtom> atom;
+  PRInt32 nsid;
+
+  aNodeInfo->GetNameAtom(*getter_AddRefs(atom));
+  aNodeInfo->GetNamespaceID(nsid);
+
+  // We still rely on the old way of setting the attribute.
+
+  return SetAttribute(nsid, atom, aValue, aNotify);
+}
+
 NS_IMETHODIMP
 nsXULElement::GetAttribute(PRInt32 aNameSpaceID,
                            nsIAtom* aName,
diff --git a/rdf/content/src/nsXULElement.h b/rdf/content/src/nsXULElement.h
index 994bcdd0be09..345dda43ffbf 100644
--- a/rdf/content/src/nsXULElement.h
+++ b/rdf/content/src/nsXULElement.h
@@ -395,6 +395,7 @@ public:
     NS_IMETHOD ParseAttributeString(const nsString& aStr, nsIAtom*& aName, PRInt32& aNameSpaceID);
     NS_IMETHOD GetNameSpacePrefixFromId(PRInt32 aNameSpaceID, nsIAtom*& aPrefix);
     NS_IMETHOD SetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, const nsString& aValue, PRBool aNotify);
+    NS_IMETHOD SetAttribute(nsINodeInfo *aNodeInfo, const nsString& aValue, PRBool aNotify);
     NS_IMETHOD GetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, nsString& aResult) const;
     NS_IMETHOD UnsetAttribute(PRInt32 aNameSpaceID, nsIAtom* aName, PRBool aNotify);
     NS_IMETHOD GetAttributeNameAt(PRInt32 aIndex, PRInt32& aNameSpaceID,