public ExtensionOperation createExtensionActivityImplementation(QName name) {
   if (name == null) return null;
   ExtensionBundleRuntime bundle = _runtime._extensionRegistry.get(name.getNamespaceURI());
   if (bundle == null) {
     return null;
   } else {
     try {
       return bundle.getExtensionOperationInstance(name.getLocalPart());
     } catch (Exception e) {
       return null;
     }
   }
 }
 public void registerExtensionBundle(ExtensionBundleRuntime bundle) {
   _contexts.extensionRegistry.put(bundle.getNamespaceURI(), bundle);
   bundle.registerExtensionActivities();
 }