Unlocking tool for your iPhone 3G or 3GS running iOS 4.2.1 to come Sunday, iPhone 4 to follow
A tweet by MuscleNerd reveals that the Ultrasn0w unlocking software for the iPhone 3G and the iPhone 3GS, running iOS 4.2.1, is making good progress, and should be available this Sunday. As usual, your device needs to be jailbroken before applying the unlocking tool, so have a look at this video tutorial how to jailbreak your iPhone, iPad or iPod touch.
Be careful not to do it prematurely before the unlock is out, though, since it updates the baseband, and will permanently reverse any prior unlocks on your iOS device. The tool will be valid for all basebands, but unlocking the iPhone 4 on iOS 4.2.1 is said to take some more time.