diff --git a/content/xul/document/src/nsXULDocument.cpp b/content/xul/document/src/nsXULDocument.cpp
index 4d993f0e0a7..df947aeb3cc 100644
--- a/content/xul/document/src/nsXULDocument.cpp
+++ b/content/xul/document/src/nsXULDocument.cpp
@@ -614,6 +614,7 @@ public:
     // nsIXULParentDocument interface
     NS_IMETHOD    GetContentViewerContainer(nsIContentViewerContainer** aContainer);
     NS_IMETHOD    GetCommand(nsString& aCommand);
+    NS_IMETHOD    CreatePopupDocument(nsIDOMElement* aPopupElement, nsIDocument** aResult); 
 
     // nsIXULChildDocument Interface
     NS_IMETHOD    SetFragmentRoot(nsIRDFResource* aFragmentRoot);
@@ -749,7 +750,7 @@ protected:
     nsString                   mCommand;
     nsIRDFResource*            mFragmentRoot;    // [OWNER] 
     nsVoidArray                mSubDocuments;     // [OWNER] of subelements
-	nsIDOMElement*			   mPopup;			  // [OWNER] of this popup element in the doc
+	  nsIDOMElement*			       mPopup;			  // [OWNER] of this popup element in the doc
 };
 
 PRInt32 XULDocumentImpl::gRefCnt = 0;
@@ -2873,6 +2874,15 @@ XULDocumentImpl::GetCommand(nsString& aCommand)
     return NS_OK;
 }
 
+
+NS_IMETHODIMP
+XULDocumentImpl::CreatePopupDocument(nsIDOMElement* aPopupElement, nsIDocument** aResult)
+{
+    *aResult = this;
+    NS_ADDREF(*aResult);
+    return NS_OK;
+}
+
 ////////////////////////////////////////////////////////////////////////
 // nsIXULChildDocument interface
 NS_IMETHODIMP 
diff --git a/rdf/content/public/nsIXULParentDocument.h b/rdf/content/public/nsIXULParentDocument.h
index e0769576ce0..2ab69d1c2a7 100644
--- a/rdf/content/public/nsIXULParentDocument.h
+++ b/rdf/content/public/nsIXULParentDocument.h
@@ -31,8 +31,12 @@ class nsIXULParentDocument: public nsISupports {
 public:
     static const nsIID& GetIID() { static nsIID iid = NS_IXULPARENTDOCUMENT_IID; return iid; }
 
+    // Used for XUL fragment child documents
     NS_IMETHOD GetContentViewerContainer(nsIContentViewerContainer** aContainer) = 0;
     NS_IMETHOD GetCommand(nsString& aCommand) = 0;
+
+    // Used for XUL popup child documents
+    NS_IMETHOD CreatePopupDocument(nsIDOMElement* aPopupElement, nsIDocument** aResult) = 0; 
 };
 
 #endif // nsIXULParentDocument_h__
diff --git a/rdf/content/src/nsXULDocument.cpp b/rdf/content/src/nsXULDocument.cpp
index 4d993f0e0a7..df947aeb3cc 100644
--- a/rdf/content/src/nsXULDocument.cpp
+++ b/rdf/content/src/nsXULDocument.cpp
@@ -614,6 +614,7 @@ public:
     // nsIXULParentDocument interface
     NS_IMETHOD    GetContentViewerContainer(nsIContentViewerContainer** aContainer);
     NS_IMETHOD    GetCommand(nsString& aCommand);
+    NS_IMETHOD    CreatePopupDocument(nsIDOMElement* aPopupElement, nsIDocument** aResult); 
 
     // nsIXULChildDocument Interface
     NS_IMETHOD    SetFragmentRoot(nsIRDFResource* aFragmentRoot);
@@ -749,7 +750,7 @@ protected:
     nsString                   mCommand;
     nsIRDFResource*            mFragmentRoot;    // [OWNER] 
     nsVoidArray                mSubDocuments;     // [OWNER] of subelements
-	nsIDOMElement*			   mPopup;			  // [OWNER] of this popup element in the doc
+	  nsIDOMElement*			       mPopup;			  // [OWNER] of this popup element in the doc
 };
 
 PRInt32 XULDocumentImpl::gRefCnt = 0;
@@ -2873,6 +2874,15 @@ XULDocumentImpl::GetCommand(nsString& aCommand)
     return NS_OK;
 }
 
+
+NS_IMETHODIMP
+XULDocumentImpl::CreatePopupDocument(nsIDOMElement* aPopupElement, nsIDocument** aResult)
+{
+    *aResult = this;
+    NS_ADDREF(*aResult);
+    return NS_OK;
+}
+
 ////////////////////////////////////////////////////////////////////////
 // nsIXULChildDocument interface
 NS_IMETHODIMP