/**
  * Overloaded execute function to handle exceptions in JSON requests
  */
 public function execute($action, KCommandContext $context)
 {
     try {
         return parent::execute($action, $context);
     } catch (KControllerException $e) {
         $this->_handleException($e);
     } catch (KModelException $e) {
         $this->_handleException($e);
     }
 }