How to user SuperSim Method with AT&T Activated iPhone

Sassha explained in this post how to use the SuperSim method to use the iPhone overseas.

I was wondering if there is anybody who has tried this on an iPhone that was legitimately activated through AT&T. Could you post modified instructions based on Sassha's tutorial?

I mainly use the iPhone in the states, however, I will be going to Germany for 3 weeks and would like to use my old Prepaid card while I am there. When I return to the states I want to continue using my AT&T service.

Any advise what I need to do different from Sassha's Tutorial would be greatly appreciated.

Why are you asking almost the SAME thing again? You already opened a new Thread with almost the same content. PLEASE stick to the original thread and don't start a new thread. Just add your additional question. Thanks. :)