public function AddItemCount($sCategoryId, $iArticleCount)
    {
        $bSet = false;
        if (array_key_exists($sCategoryId, $this->aContainingChildCategories)) {
            $this->iAllItemCount = $this->iAllItemCount + $iArticleCount;
            if (!is_null($this->oChildCategoryTreeList)) {
                $this->oChildCategoryTreeList->GoToStart();
                while ($oChildCategoryTree = $this->oChildCategoryTreeList->Next()) {
                    if (!$bSet) {
                        $bSet = $oChildCategoryTree->AddItemCount($sCategoryId, $iArticleCount);
                    }
                }
            }
        } else {
            if (!is_null($this->oRealCategory) && $sCategoryId == $this->oRealCategory->id) {
                $this->iAllItemCount = $iArticleCount;
                $bSet = true;
            }
        }

        return $bSet;
    }