public function register()
    {
        $this->helper_callbacks = array();
        $arguments= func_get_args();
        if(count($arguments) > 0){
            foreach($arguments as $argument){
                if($argument instanceof Plugin){ //this is a plugin object
                    $callback = $argument->getEventHelperCallback($this->getName());
                    if(is_callable($callback)){
                        $this->helper_callbacks[] = $callback;
                    }                 
                }
                else if(is_callable($argument)){ //this is a closure
                    $this->helper_callbacks[] = $argument;
                }
            }
        }

        return $this; //return the event object reference to allow chainable calls
    }