protected function _getVersion($component)
    {
        if (!isset(self::$_versions[$component]))
        {
            try
            {
                if ($component === 'koowa') {
                    $version = Koowa::VERSION;
                }
                else $version = $this->getObject('com://admin/' . $component.'.version')->getVersion();
            }
            catch (Exception $e) {
                $version = null;
            }

            self::$_versions[$component] = $version;
        }

        return self::$_versions[$component];
    }