I've been scouring the web and have not found quite the right answer or style of answer I am looking for. I don't want to unlock or jailbreak, I want to stay stock for now. So, my question: I had an iPhone 2G. I recently bought a 3GS. It had a SIM card in it, but I didn't think about it and put in my 2G's SIM. I recently noticed that MMS is not functioning for me, but 3G service is. So my question is this: 1) is it possible to activate the newer SIM? Inserting it doesn't offer an activate screen in iTunes, all I get is no bars up top on the screen. 2) is there any validity to the fact that MMS isn't working because I have the old SIM? On my bill, they still have me on the 2G iPhone plan– unlimited internet with 200 messages. Could that be it? I know for certain that there are plenty of people around here with muuuuch more knowledge than me, and I want to tap that knowledge. Thanks guys!