How many other people are using their iPhone 3G S with a prepaid SIM? I had the original iPhone gen 1 and upgraded to the 3G S. The account deposit ATT asked me for to go post paid was higher than the $699 no contract price. So I went ahead and bought it no contract. When I got home I just pulled the SIM out of my old iPhone and popped it into the 3G S. It said connect to iTunes to activate. I did and it activated with the prepaid SIM. The ATT rep INSISTED this would not work saying the iPhone only worked post paid. They are so full of crap. My 3G S is working fine prepaid.