I had put AppTapp on my iPhone pretty early on, and then when the 1.1.1 debacle happened I decided to take it back to factory settings and update. I figured I'd have to eventually and I didn't want to have to worry about my phone breaking when I was forced to update later on. Everything is working fine, I've had no problems with the 1.1.1 firmware up until today and I updated a few days after it came out. Today after hanging up a call I get an error message saying something like "Invalid SIM inserted." I tried to make a call and I get another error saying "Call failed, Invalid SIM inserted." I was pretty freaked out, but mostly I was pissed because the update had gone fine and the phone was working normally. I restarted the phone, got nothing. Turned the phone off, took out the AT&T SIM card, reinserted, turned it on, and everything was fine. WTF? This seems pretty bad, especially because it is my only phone. Has anyone seen anything like this? Do you think it warrants a trip to the Apple store for an exchange? Thanks for reading.