Below step wise guide helps you to unlock your iPhone 4 and iPhone 3GS on iOS 5.1.1 the latest ios version. The unlock is compatible with the following basebands:
Before unlock you must jailbreak 5.1.1 on iPhone 4 and iphone 3gs. If you have not jailbroken just visit this tutorial on “How to jailbreak iOS 5.1.1” then follow below steps for iphone unlock:
Note: The current ios 5.1.1 jailbreak is tethered therefore be careful while jailbreaking.
How to Unlock iPhone on iOS 5.1.1
Step 1: Add the new repository to your Cydia. Open Cydia and go to => Manage tab =>Sources => tap the edit button on top right => Tap add button = > Type http://repo.iparelhos.com in the window => Tap add Source
Step 2: After the source is successfully added you will find iparelhos in the list of resources, just tap it and now you will find “UltraSn0w Fixer for 5.1.1. Just tap it and install.
Step 3: Now open main Cydia window and go to search section type Ultrasn0w and Install it. Let the installation complete. After the iPhone is rebooted now it is unlocked. Enjoy.