The dev team has released a new unlocking tool for the iPhone to unlock iPhone 3G and 3GS. PwnageTool 4.1.3 unlocks iPhone devices with baseband later than 05.13.04. The new hack for the AT+XMPP exploit requires users to upgrade to baseband 06.15.00 before attempting an unlock.
PwnageTool 4.1.3 will unlock devices which includes iPhone 3G, iPhone 3GS and the 3G based iPad. However, iPad users will have to download firmware 3.2.2 to upgrade their baseband.
Certainly don’t update to 06.15 if you don’t need to! Only do this if you need the unlock and you’re stuck on 05.14 or 05.15, and you’re willing to assume the above risks.
An unlock for iPhone 4 is not yet available, however, this should be available in the next few weeks. Please note that there is no way to come back down from 06.15, and there’s no hiding the baseband version from Apple. So this will void your warranty so make your decisions very carefully.
This PwnageTool also contains a 4.2.1 bundle for iPhone3G ownersâ€¦for all else, it’s still only 4.1. If you have an iPhone3GS with an old bootrom, the new redsn0w will handle 4.2.1 for you (in fact it covers 4.2.1 for all devices, even though some of them are still tethered at 4.2.1 until @comex can work some untethering magic). iPhone3GS users with old bootroms who want to go to 4.2.1 should not use this PwnageTool! Update to stock 4.2.1 first, then use the upcoming redsn0w to update your baseband.
Currently the unlock is only available for Mac users, but a Windows unlock should be on its way soon.