public static function clearCache(modX $modx) {
        $cacheKey= 'namespaces';
        $cleared = $modx->cacheManager->delete($cacheKey, array(
            xPDO::OPT_CACHE_KEY => $modx->getOption('cache_namespaces_key', null, 'namespaces'),
            xPDO::OPT_CACHE_HANDLER => $modx->getOption('cache_namespaces_handler', null,$modx->getOption(xPDO::OPT_CACHE_HANDLER)),