diff --git a/content/base/src/nsGenericElement.cpp b/content/base/src/nsGenericElement.cpp
index 70db612ef23d..42473a9be46f 100644
--- a/content/base/src/nsGenericElement.cpp
+++ b/content/base/src/nsGenericElement.cpp
@@ -287,7 +287,7 @@ NS_IMETHODIMP
 nsDOMAttribute::GetOwnerDocument(nsIDOMDocument** aOwnerDocument)
 {
   // XXX TBI
-  return NS_OK;
+  return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 //----------------------------------------------------------------------
diff --git a/layout/base/src/nsGenericElement.cpp b/layout/base/src/nsGenericElement.cpp
index 70db612ef23d..42473a9be46f 100644
--- a/layout/base/src/nsGenericElement.cpp
+++ b/layout/base/src/nsGenericElement.cpp
@@ -287,7 +287,7 @@ NS_IMETHODIMP
 nsDOMAttribute::GetOwnerDocument(nsIDOMDocument** aOwnerDocument)
 {
   // XXX TBI
-  return NS_OK;
+  return NS_ERROR_NOT_IMPLEMENTED;
 }
 
 //----------------------------------------------------------------------