The following step-by-step tutorial/guide will help you unlock your iPhone 3G and iPhone 3GS with the latest iPhone 3.1.2 firmware using ultrasn0w. This unlocking guide applies to iPhone 3G and 3GS only. This unlocking guide will work for you only if your Modem Firmware (Baseband) version is 04.26.08. Follow the step-by-step instructions below to unlock your iPhone on firmware 3.1.2.