I have a jailbroken and untethered 3G phone that a friend is now using . No more Rogers. He is now using Telus up here in Canada. The problem is with the iOS 3.1.3 under settings --> genearl --> network, there is no switch to turn off cellular data as there is on the iPhone 4. I have tried turning off the wireless and the 3G iPhone definitely is accessing cellular data as it is able to open new web pages. My friend doesn't want the expense of paying for data at all. How can we turn it off? Any help would be greatly helpful. In order to jailbreak and untether the 3G I used Spirit jb and then Cydia with ultrasn0w. All that worked out great then I got a Telus sim and that worked too. The only thing now is the cellular data and turning it off.