The unofficial iPhone Dev Team has posted ultrasn0w 1.0-1, an update of its unlocking utility. The release is the first to unlock the iPhone 4, in addition to the iPhone 3G and 3GS. iPhone 4s must be on the 01.59 baseband, while the 3G and 3GS must be using 04.26.08, 05.11.07, 05.12.01 or 05.13.04.