The unlock for iOS 4.0 was released immediately after it went live, this could be fastest unlock from iPhone dev team but release of iOS 4.0.1 could have spoiled all fun. It is surprising to see Apple didn’t update the baseband in iOS 4.0.1 and it is same as iOS 4.0 Baseband 05.13.04 meaning users can update to iOS 4.0.1 without fear of getting locked and same is confirmed by iPhone dev team member Musclenerd. Users with iOS 4.0.1 can unlock iPhone 3G & iPhone 3GS with Ultrasn0w 0.93.
We have already covered guide on how to jailbreak iOS 4.0.1 on iPhone 3G & iPod Touch 2G now here is step by step guide to unlock iOS 4.0.1 on iPhone 3G & iPhone 3GS.
Please Note: T-Mobile USA users must disable 3G before proceeding to unlock iOS 4.0 on iPhone 3G & 3GS.
How to Unlock iOS 4.0.1 Baseband 05.13.04 on iPhone 3G/3GS
1. Jailbreak iOS 4.0.1 using Redsn0w 0.9.5 Beta 5
2. Now start Cydia and go to Manage section
3. Now click on sources and click on edit to add following repo
Repo666.ultrasn0w.com (it’s ‘0(zero)’ and not ‘o’)
4. Now search for Ultrasn0w 0.93 and click on install
5. Let Ultrasn0w 0.93 to complete unlocking
iPhone will reboot after ultrasn0w completes its process. Now enjoy your unlocked iPhone 3G/3GS 4.0.1 with your favorite carrier.