public static function GetActiveRootCategory()
    {
        static $oActiveRootCategory = 'x';
        if ('x' === $oActiveRootCategory) {
            $oActiveRootCategory = null;
            $oActiveCategory = self::getShopService()->GetActiveCategory();
            if (null !== $oActiveCategory) {
                $oActiveRootCategory = $oActiveCategory->GetRootCategory();
            }
        }

        return $oActiveRootCategory;
    }