The current version of Miva Merchant is Merchant5-PR3-bundle.tar and is included with package #4. There is a $149 upgrade fee from an earlier version, unless you have received a free upgrade notice from Miva Corp.
Miva Merchant is an advanced shopping cart system which can integrate with automated payment processing systems. Some Domain Support accounts come bundled with the Miva Merchant shopping cart. To find out more about Miva Merchant you can go to the Miva web site at http://www.miva.com/
Demo Visit the Miva Merchant Demo
Also visit the Miva Galleria for other examples of actual Miva Merchant implementations.
Real-Time payment processing with Miva Merchant To fully take advantage of Miva Merchant you will need a merchant bank account and credit card processing service.
Miva Merchant supports the following 3rd party processors for real-time credit card transactions(you would still need a bank merchant account which you can likely obtain from your local bank):
Cardservice International/Link Point Gateway