protected static function _getTagList() {
        $config = Zend_Registry::get('config');
        if (!empty($config->staticcaching->tags)) {
            return $config->staticcaching->tags;
        }

        // For backward-compatibility: fall back to a separate cache.ini
        $ini = new Garp_Config_Ini(APPLICATION_PATH . '/configs/cache.ini', APPLICATION_ENV);
        if (!empty($ini->tags)) {
            return $ini->tags;
        }

        return null;
    }