It appers that Surepay are no longer developing nor enhancing the gateway interface after they joined verisign, according to this FAQ: http://www.surepay.com/index.cfm?fuseaction=merchantpayments.surepay_payment_gateway.faq.partnership_verisign
So, I really don't see much point in developing the SauSurepay class and documentation any further, as the user base will not grow anymore and most likely vanish in a few years.
However, there may be some other similar services that this class can be adopted and customized to fit, if I see a need (usually my clients give me those tasks), I may start another project using this as a base...
A little hack for PHPshop 0.6.1 enables you to use the SauSurePay library directly from PHPshop to process Credit card and TeleCheck requests.
This new version has a totally changed API, its now all in one class and no need to keep track of what XML strings belongs where. In fact, this lib now holds all your added data in 'Objects', Well, its in an array, but future versions may use objects or DOM of some kind, but that will be transparent to the script using it. This script should be a great improvement.
I just finished a new version of the library. The API is totally change, hopefully to the better. It will be a lot easier to make functions that interract with other systems. I have made a hack for PHPshop to use sau-surepay as well, it will be posted here in a couple of days, just got'a get the worst bugs out.
This first release was created because of a project in need for some functionality. Therefor, only the functions/classes needed for this project is added in, but the potential to add more functions to support every type of SurePay.Com's commands is there.