The Ultrasn0w 1.0-1 has been released to unlock iPhone 4 on iOS 4.0/4.0.1 firmwares.
Prior to this release, last day the JailbreakMe tool was released by Comex to jailbreak the iPhone 4. You could use it to jailbreak your iPhone 4 and then unlock it using Ultrasn0w 1.0-1.
If you want to unlock iPhone 4 4.0/4.0.1, then here is how to do it using Ultrasn0w 1.0-1. Below written are the instructions to unlock iPhone 4 on iOS 4.0/4.0.1 with Ultrasn0w 1.0-1.
1. Jailbreak your iPhone 4 using JailbreakMe.
2. Open Cydia.
3. Select the ” Manage ” tab at the bottom of the screen.
4. Now select the ” Sources ” option.
5. Tap on ” Edit ” and then on ” Add “.
6. Now type in ” http://repo666.ultrasn0w.com ” and tap on ” Add Source “.
7. Let Cydia update the sources. Wait for it to complete.
8. Now search for Ultrasn0w 1.0-1 in Cydia using the search field.
9. Install Ultrasn0w 1.0-1 from the list to unlock iPhone 4 4.0/4.0.1.
10. Reboot your phone to completely unlock iPhone 4 4.0/4.0.1.
That’s it! Now you can enjoy your completely unlocked iPhone 4.