The ultrasn0w 0.93 has just been released by iPhone Dev Team to unlock all iPhone having baseband 05.13.04 (on iOS 4) or 05.12.08 (on 3.1.3). Full instructions to unlock iPhone using this tool has been posted below.

To unlock you iPhone using this ultrasn0w unlocking tool, first you must need to have a fully jailbroken device.

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Unlock Baseband 05.13.04 / 05.12.01 – How to

Just follow the step by step guide posted below to unlock both baseband that is 05.13.04 (on iOS 4) and 05.12.01 (on 3.1.3):

Note: To follow the guide posted below, you must need to have iPhone running jailbroken firmware.

1. Launch “Cydia” on your iPhone
2. Go to “Manage” and then to “Sources”
3. Press “Edit” and then “Add”
4. Now it will ask you to enter a “Cydia/APT URL” source
5. In that box type “repo666.ultrasn0w.com“, then press “Add Source”
6. Now your Cydia source will automatically be updated
7. After the update is completed, in Cydia, search for “ultrasn0w 0.93″ and then install that app. This app will automatically unlock your iPhone
8. Now restart your iPhone
9. When your iPhone boot up, it should be fully unlocked and can be used with any carrier