Follow it.....
- Open Cydia From your iPhone
- Now Select Sources Option
2. Now Tap on Edit Button Add Repo “
Repo666.UltraSn0w.Com” And now Touch on Add Source button. As seen in the Screenshot.
3. Now Cydia will update the source automatically. When the update is complete go into the search tab and search
“ultrasn0w 1.2″. After Installing that you will be able to use your iPhone with any carrier of your choice.
Almost done, now simply reboot your iPhone and you should have a fully unlocked iPhone 3GS on iOS 4.1 or iOS 4.2.1.
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