Just to be clear: this is not a new unlock. It’s simply a fix for ultrasnow to work on the already supported basebands.
So, a few days after iOS 5 official release to the public, the iPhone Dev Team updated their ultrasn0w unlock tool to 1.2.4 version to bring support for Apple’s new iOS 5.0 software update. However, on iOS 5.0.1 release, the team didn’t update their tool. That’s why some other hackers could make a “Fix for Ultrasn0w” on iOS 5.0.1.
In this guide I’ll show you how to unlock iPhone 4 or iPhone 3GS running iOS 5.0.1 using ultrasn0w. You’ll need a jailbroken device on iOS 5.0.1, you can follow our guide posted here to jailbreak iPhone 4 and iPhone 3GS on iOS 5.0.1.
How To Unlock iPhone 4, iPhone 3GS On iOS 5.0.1
STEP 1: Open Cydia from your device.
STEP 2: Head to Manage, Sources, Edit, Add then write down the following repository:
STEP 3: Now get back to the source and you’ll find two ultrasn0w fixers, one for the iPhone 4 and the other to the iPhone 3GS.
STEP 4: Choose the suitable one and install it.
Okay, you’re done now! Just give your device a reboot and you’ll be well to go.
For those wondering about iPhone 4S unlock, there’s a “very promising” iPhone 4S unlock in the works by the iPhone Dev Team.
Let us know if you need further help.
UPDATE: The above repository seems to be not working for some people due to servers overload, you can try this repo instead: