/**
  * getModelCategories
  * @return Model_Categories
  * @author Cornelius Hansjakob <*****@*****.**>
  * @version 1.0
  */
 private function getModelCategories()
 {
     if (null === $this->objModelCategories) {
         /**
          * autoload only handles "library" compoennts.
          * Since this is an application model, we need to require it
          * from its modules path location.
          */
         require_once GLOBAL_ROOT_PATH . $this->core->sysConfig->path->zoolu_modules . 'core/models/Categories.php';
         $this->objModelCategories = new Model_Categories();
         $this->objModelCategories->setLanguageId($this->core->sysConfig->languages->default->id);
     }
     return $this->objModelCategories;
 }