I had upgraded to 3.1, not realizing the problem it would cause with my Garmin bluetooth. I did manage to downgrade back to 3.0 but the baseband is still 5.11, which I think is what causes the problems with the bluetooth. So I've already gone this far, just gonna go buy another iphone at att with an older manufacture date, assuming that what I've read about the 4-5 digits in serial number indicating manufacture date. It doesn't look like there's going to be a fix for the bluetooth issue with gps systems anytime soon...bah-humbug
trisha