Do I need to unlock my iPhone 2G to use an iPhone 3G Sim? Noobish question I know, but better safe than sorry! I have a jailbroken iPhone 2G locked to O2 and am contemplating on buying an unactivated iPhone 3G Sim for the O2 12 month free Web & WiFi bolt-on. Would I need to unlock my iPhone to be able to use the 3G sim? Also if so, is it possible to unlock the iPhone after the jailbreak or would I need to restore the iPhone and jailbreak again but this time with the unlock function. Thanks.