protected function _changeParent(Model $model, $id = null, $parentId = null) {
		$parentField = $this->_getBehaviorConfig($model, 'parent');
		if (empty($id) || ($parentField === null)) {
			return false;
		}

		$model->recursive = -1;
		$treeItem = $model->read(null, $id);
		if (empty($treeItem)) {
			return false;
		}

		$treeItem[$model->alias][$parentField] = $parentId;
		$result = (bool)$model->save($treeItem);

		return $result;
	}