I'm sorry but I checked for the answer and haven't had any luck finding it yet. Maybe you nice people can help me out.
My Brother bought an iPhone and has a very good plan with AT&T that he would like to keep. Can he activate his current AT&T SIM card with the iPhone? I know you can't with any other SIM unless using TurboSim or the Hardware unlock. But I'm pretty sure you can use a regular AT&T Sim.