protected function directiveAddOption($line)
    {
        if (preg_match('/^(\s+):(.+): (.*)$/mUsi', $line, $match)) {
            $this->directive['options'][$match[2]] = trim($match[3]);
            return true;
        } else if (preg_match('/^(\s+):(.+):(\s*)$/mUsi', $line, $match)) {
            $value = trim($match[3]);
            $this->directive['options'][$match[2]] = true;
            return true;
        } else {
            return false;
        }
    }