diff --git a/mozilla/extensions/xforms/nsXFormsModelElement.cpp b/mozilla/extensions/xforms/nsXFormsModelElement.cpp
index 7d0099f059a..ab8a06dded9 100644
--- a/mozilla/extensions/xforms/nsXFormsModelElement.cpp
+++ b/mozilla/extensions/xforms/nsXFormsModelElement.cpp
@@ -1548,6 +1548,7 @@ nsXFormsModelElement::ValidateDocument(nsIDOMDocument *aInstanceDocument,
   nsCOMPtr<nsIDOMElement> element;
   nsresult rv = aInstanceDocument->GetDocumentElement(getter_AddRefs(element));
   NS_ENSURE_SUCCESS(rv, rv);
+  NS_ENSURE_STATE(element);
 
   // get namespace from node
   nsAutoString nsuri;