/**
  * Attempts to introspect the correct values for object properties including
  * $userModel and $sessionKey.
  *
  * @param object $controller A reference to the instantiating controller object
  * @return boolean
  */
 protected function _setDefaults()
 {
     $result = parent::_setDefaults();
     if (!empty($this->userModel)) {
         list($plugin, $class) = pluginSplit($this->userModel, null, true);
         App::uses($class, $plugin . 'Model');
         static::$documentModel = $class;
     }
     return $result;
 }