Hey guys, Today alone, I've had to reboot my iPhone 4 a dozen times because a "no SIM" message keeps popping up. I'm running iOS 4.1. It happens when I'm on the phone, using the web and when the phone is inactive on my desk. I had this issue when I first got the phone and AT&T replaced my SIM card twice. Any idea what causes this? I plan on going to an Apple Store tomorrow to get it looked at, but if they end up swapping my phone, will I be able to jailbreak the iOS loaded on there?