Ultrasn0w 1.2 unlock is now available in Cydia. It comes with bit of twist as it can unlock iPhone 3GS 4.2.1 and iPhone 3G 4.2.1 but can’t unlock 05.15.04 or 05.14.02 baseband. As a workaround, PwnageTool 4.1.3 lets you update iPhone 3GS, 3G to 06.15.00 baseband. Apparently ultrasn0w 1.2 can unlock 06.15.00 that actually is iPad 3.2.2 baseband. First your baseband is updated and then it’s unlocked, that’s as complex as it sounds. You can unlock your devices anyway, here is the guide:
How to Unlock iPhone 3GS, 3G 4.2.1 iOS
Step 1: Jailbreak iPhone 3GS 4.2.1 and also update baseband to 06.15.00 in the process.
Step 2: Run Cydia from SpringBoard.
Step 3: Tap on “Edit”, then hit “Add”, a prompt should appear asking “Enter Cydia/APT URL”.
Step 4: Enter http://repo666.ultrasn0w.com/ and hit “Add Source”, then tap on “Return to Cydia”.
Step 5: Once the process completes, search for ultrasn0w 1.2 in Cydia and install it.
Step 6: After installation, reboot your iPhone. That’s it!
Enjoy your unlocked iPhone.
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