/**
  * 
  * @return boolean True if APCu is installed as an extension and is enabled in php.ini
  */
 public static function configure_apc()
 {
     $isApcEnabled = extension_loaded('apc') && ini_get('apc.enabled') == 1;
     if (!$isApcEnabled) {
         return false;
     }
     SS_Cache::add_backend(CACHEABLE_STORE_NAME, 'Apc');
     self::$current_mode = 'apc';
     return true;
 }