protected function unserializeError()
    {
        if (!$error = call_user_func($this->errorGetter)) {
            return false;
        }

        if ($error['file'] != __FILE__) {
            return false;
        }

        if (strpos($error['message'], 'unserialize(') !== 0) {
            return false;
        }

        return $error['message'];
    }