/**
  * @see Doctrine_Record::unlink()
  * @return sfCachetaggableDoctrineRecord
  */
 public function unlink($alias, $ids = array(), $now = false)
 {
     $self = parent::unlink($alias, $ids, $now);
     try {
         $taggingCache = sfCacheTaggingToolkit::getTaggingCache();
     } catch (sfException $e) {
         return $self;
     }
     $tagNames = $this->getTagNamesByAlias($alias, $ids);
     if (is_array($tagNames)) {
         $taggingCache->deleteTags($tagNames);
     }
     return $self;
 }