function getExtended($nameOrAlias)
    {
        while ($this->isExtendedService($nameOrAlias)) {
            $cAlias      = $this->_normalizeName($nameOrAlias);
            $nameOrAlias = $this->aliases[$cAlias];
            ## check if we have alias to nested service
            if (strpos($nameOrAlias, self::SEPARATOR) !== false)
                // we have an aliases that used as
                // share services between nested services
                // in form of "/filesystem/system/folder"
                // that mean, service is alias from "/filesystem/system/" for "folder" service
                break; ## so break iteration
        }

        return $nameOrAlias;
    }