function isValid($key, $hash, $salt)
 {
     try {
         $privKey = X_VlcShares_Plugins_Cache::forcedRetrieveItem("threads-requestkey::{$hash}");
         return md5("{$salt}{$privKey}{$key}") === $hash;
     } catch (Exception $e) {
         // no cache entry? invalid for sure...
         return false;
     }
 }
 function clearoldAction()
 {
     $this->plugin->clearInvalid();
     $this->_helper->flashMessenger(array('type' => 'success', 'text' => X_Env::_('p_cache_clearolddone')));
     $this->_helper->redirector('index', 'manage');
 }