As a user of this contribution, while I see there is a commercial update available, I felt it important to keep the community GNU version relevant and useful so I have updated it to comply with SagePay Protocol v3.00 minimum requirements and tested it with Sage Pay on ZC 1.50, 1.51 and 1.52 with no problems.

I have submitted the updates to this site as version 2.1. https://www.zen-cart.com/downloads.php?do=file&id=1453

In the mean time if anyone is desperate for updates to Protocol v3.00 for their store, please feel free to message me.

Andrew