public function assert(Zend_Acl $acl, Zend_Acl_Role_Interface $user = null, Zend_Acl_Resource_Interface $store = null, $privelege = null)
 {
     // check for a link in the link table
     $linksMapper = new Application_Model_Mapper_Stores_StoresUsersLinksMapper();
     $link = $linksMapper->findLink($store->storeID, $user->userID);
     if (!$link) {
         return false;
     }
     // check for certain priveleges based on linkRole
     if ($privelege == 'update') {
         if ($link->linkRole != 'admin') {
             return false;
         }
     }
     return true;
 }