diff --git a/mozilla/content/base/src/nsDocument.cpp b/mozilla/content/base/src/nsDocument.cpp
index cfccb8a7b19..8fca77bf109 100644
--- a/mozilla/content/base/src/nsDocument.cpp
+++ b/mozilla/content/base/src/nsDocument.cpp
@@ -2109,11 +2109,12 @@ nsDocument::CreateElement(const nsAString& aTagName,
   nsresult rv = nsContentUtils::CheckQName(aTagName, PR_FALSE);
   NS_ENSURE_SUCCESS(rv, rv);
 
-  NS_ConvertUTF16toUTF8 tmp(aTagName);
-  if (!IsCaseSensitive()) {
-    ToLowerCase(tmp);
-  }
-  nsCOMPtr<nsIAtom> name = do_GetAtom(tmp);
+  NS_ASSERTION(IsCaseSensitive(),
+               "nsDocument::CreateElement() called on document that is not "
+               "case sensitive. Fix caller, or fix "
+               "nsDocument::CreateElement()!");
+
+  nsCOMPtr<nsIAtom> name = do_GetAtom(aTagName);
 
   nsCOMPtr<nsINodeInfo> nodeInfo;
   rv = mNodeInfoManager->GetNodeInfo(name, nsnull, GetDefaultNamespaceID(),
diff --git a/mozilla/content/html/document/src/nsHTMLDocument.cpp b/mozilla/content/html/document/src/nsHTMLDocument.cpp
index d4f687b453a..70133ccc1ed 100644
--- a/mozilla/content/html/document/src/nsHTMLDocument.cpp
+++ b/mozilla/content/html/document/src/nsHTMLDocument.cpp
@@ -1387,7 +1387,30 @@ NS_IMETHODIMP
 nsHTMLDocument::CreateElement(const nsAString& aTagName,
                               nsIDOMElement** aReturn)
 {
-  return nsDocument::CreateElement(aTagName, aReturn);
+  *aReturn = nsnull;
+
+  nsresult rv = nsContentUtils::CheckQName(aTagName, PR_FALSE);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  nsAutoString tmp(aTagName);
+
+  if (!IsXHTML()) {
+    ToLowerCase(tmp);
+  }
+
+  nsCOMPtr<nsIAtom> name = do_GetAtom(tmp);
+
+  nsCOMPtr<nsINodeInfo> nodeInfo;
+  rv = mNodeInfoManager->GetNodeInfo(name, nsnull, mDefaultNamespaceID,
+                                     getter_AddRefs(nodeInfo));
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  nsCOMPtr<nsIHTMLContent> content;
+  rv = NS_CreateHTMLElement(getter_AddRefs(content), nodeInfo, IsXHTML());
+  NS_ENSURE_SUCCESS(rv, rv);
+  content->SetContentID(mNextContentID++);
+
+  return CallQueryInterface(content, aReturn);
 }
 
 NS_IMETHODIMP