Hey guys, i know that there are many of us trying to get this to work, i have spent several days trying to figure it out and finally i did.
Theres no need to call AT&T and have WAP enabled or pushed.
I have a razor motorola phone, all i did was take the SIM card from my IPHONE 3G and insert it into the RZOR. Then i went to the MEdia NEt website for AT&T and registered my number there while the SIM CARD was still inside the RZOR phone, once i did that, i placed a couple of calls with the rzor and then removed the sim card.
Placed it back into the iphone, and VOILA!! is working!! sending and receiving pictures.