protected function _checkType( $value )
	{
		switch( $value )
		{
			case MShop_Order_Item_Abstract::TYPE_REPEAT:
			case MShop_Order_Item_Abstract::TYPE_WEB:
			case MShop_Order_Item_Abstract::TYPE_PHONE:
				break;
			default:
				throw new MShop_Order_Exception( sprintf( 'Order type "%1$s" not within allowed range', $value ) );
		}
	}