public static function &GetRootCategoryList($sLanguageID = null)
    {
        if (null === $sLanguageID) {
            $sLanguageID = self::getMyLanguageService()->getActiveLanguageId();
        }
        $sRestriction = "(`shop_category`.`shop_category_id` = '0' OR `shop_category`.`shop_category_id` = '')";
        $sCategoryRestriction = TdbShopCategoryList::GetActiveCategoryQueryRestriction();
        if (!empty($sCategoryRestriction)) {
            $sRestriction = $sRestriction.' AND '.$sCategoryRestriction;
        }
        $sQuery = self::GetDefaultQuery($sLanguageID, $sRestriction);

        return TdbShopCategoryList::GetList($sQuery, $sLanguageID);
    }