public function isWritable()
        {
                if (file_exists($this->phpids_base.self::FILENAME_RULES) &&
                        is_writable($this->phpids_base.self::FILENAME_RULES) &&
                        file_exists($this->phpids_base.self::FILENAME_CONVERTER) &&
                        is_writable($this->phpids_base.self::FILENAME_CONVERTER)) {
                        return true;
                } else {
            return false;
                }

        }