We have informed you about the availability of ultrasn0w 1.2.1 with the unlock support of iOS 4.3.1 that works with the old basebands. Here, we will guide you how to unlock your iPhone 4 or iPhone 3GS running on iOS 4.3.1 using ultrasn0w 1.2.1.
Here, I will guide you how to Jailbreak your iPhone 3.0 (2G 3G 3GS) with Redsn0w Method. This method can also used to jailbreak iPhone 2G. Before following the guide, you must know that Redsn0w method only work on Windows Operating System.