/**
  * parent::output() is a protected method, only way to access it from a
  * callback in php5.3 is to make a public function. In 5.4 can replace with
  * a Closure.
  *
  * @param string $out
  * @param mixed $channel
  */
 public function output($out, $channel = null)
 {
     parent::output($out, $channel);
 }