protected function _setWhereClause(Zend_Db_Select &$select, $slugField, $slug, Garp_Model_Db $model, $lang = null) {
        $slugField = $model->getAdapter()->quoteIdentifier($slugField);
        $select->reset(Zend_Db_Select::WHERE)
            ->where($slugField . ' = ?', $slug);
        if ($lang) {
            $select->where(Garp_Model_Behavior_Translatable::LANG_COLUMN . ' = ?', $lang);
        }
    }