diff --git a/mozilla/extensions/python/xpcom/src/PyXPCOM.h b/mozilla/extensions/python/xpcom/src/PyXPCOM.h
index 4987d0b3f1f..db1e82555a8 100644
--- a/mozilla/extensions/python/xpcom/src/PyXPCOM.h
+++ b/mozilla/extensions/python/xpcom/src/PyXPCOM.h
@@ -424,7 +424,7 @@ private:
 class PYXPCOM_EXPORT PyXPCOM_GatewayWeakReference : public nsIWeakReference {
 public:
 	PyXPCOM_GatewayWeakReference(PyG_Base *base);
-	~PyXPCOM_GatewayWeakReference();
+	virtual ~PyXPCOM_GatewayWeakReference();
 	NS_DECL_ISUPPORTS
     NS_DECL_NSIWEAKREFERENCE;
 	PyG_Base *m_pBase; // NO REF COUNT!!!