I just got my discount pricing from AT&T and want to go from my 3g to 3gs. If I walk into a store and buy one, can I jailbreak it? Do they upgrade the firmware on their stock or flash them when the customers get them? The store agreed to let me look at the phone before purchase, what should I look for? I have a friend there. What firmware is 100% breakable? I have no interest in iphone 4.0. Thanx..