I am having a problem getting my ATT blackberry sim (data part, phone works) to work on my iPhone 3G. I jailbroke the phone, than unlocked it using Ultrasn0w and changed the APN to Cingular to use their data service and it just says searching at the top and niether the phone or internet will work with my ATT blackberry sim card.

Can anyone tell me how to get this to work, I need to use my ATT blackberry sim for my iPhone 3G and us the blackberry data plan. Thanks for your help.