public function AddArticle($sArticleId, $dAmount = 1, $sComment = null)
    {
        $dNewAmount = 0;
        $aItemData = array();
        $oItem = TdbPkgShopWishlistArticle::GetNewInstance();
        /** @var $oItem TdbPkgShopWishlistArticle */
        if ($oItem->LoadFromFields(array('pkg_shop_wishlist_id' => $this->id, 'shop_article_id' => $sArticleId))) {
            $aItemData = $oItem->sqlData;
            $aItemData['amount'] += $dAmount;
        } else {
            $aItemData['pkg_shop_wishlist_id'] = $this->id;
            $aItemData['shop_article_id'] = $sArticleId;
            $aItemData['amount'] = $dAmount;
            $aItemData['datecreated'] = date('Y-m-d H:i:s');
        }
        if (!is_null($sComment)) {
            $aItemData['comment'] = $oItem->LoadFromRow($aItemData);
        }
        $oItem->LoadFromRow($aItemData);
        $oItem->AllowEditByAll(true);
        $oItem->Save();
        $dNewAmount = $aItemData['amount'];

        return $dNewAmount;
    }