As you know Apple dropped iOS 4.0.1 for iPhone 3G, iPhone 3GS and iPhone 4 in response to wrong signal calculation. This is a minor update and no major changes in baseband update and jailbreak protection, at least for iPhone 3G. We already posted a complete how to guide on how to Jailbreak iOS 4.0.1 for iPhone 3G with Redsn0w. Following are the instructions to unlock iPhone 3G with iOS 4.0.1
Note : Ultrasn0w is being updated to fix Mobilesubstrate issue, hold for a little while.
Instructions to install ultrasn0w using cydia
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