I have a situation with ATT. I am a big phone enthusiast and pretty much have owned and/or tried most of the cool phones out there, though I always revert back to the iphone which is the best. My thing is i'll buy a new phone and sell my old phone. So to date ive probably went thru 5-7 different iphones (1st gen and 3g). I always keep my data plan correct with ATT cause im scared of getting charged extra on data. So everytime I go to a blackberry i'll get their data plan, or if I use a unlocked phoned i'll get the unlimited plan. By now i've switched back to the iphone plan too many times and ATT wont allow me to hook up another iphone, which they state is a new policy because of all the unlocked iphones out there and people buying the iphone from them then canceling. They allow 3 different iphone imei's per 2-year contract, and me being about 6 months in, i'd have to wait 1.5 years before I could legitimately hook up an iphone to the correct data plan. Though they didnt state if this is only for the 3g or 1st gen as well. Anyways, Im currently on a blackberry plan w/ att and will be selling my blackberry, and I have 2 other phones, a g1 and 1st gen iphone (Both Unlocked). I was thinking of getting the unlimited data/text plan and giving my g1's imei to att and having that as my main phone. But if I swap sim cards from that g1 to the unlocked iphone, will ATT know im using it? Furthermore, would I be able to use data on the iphone okay because the plan is unlimited, dont really care about visual voicemail so thats not an issue for me. Or if anyone out there knows if that policy I spoke of is only for the 3g and not the 1st gen. I prefer the 1st gen iphone data plan cause its cheaper and I can use the g1 w/ that as well. Sorry for the long read but i've been doing a search all morning and couldn't really find an exact answer or someone who has a similar situation as me. Any info would help greatly.