public function isImplemented( $what )
	{
		switch( $what )
		{
			case MShop_Service_Provider_Payment_Abstract::FEAT_CAPTURE:
			case MShop_Service_Provider_Payment_Abstract::FEAT_QUERY:
			case MShop_Service_Provider_Payment_Abstract::FEAT_CANCEL:
			case MShop_Service_Provider_Payment_Abstract::FEAT_REFUND:
				return true;
		}

		return false;
	}