The iOS firmware was released a day before and the jailbreak guide for the iPhone 3GS on iOS 4.1 firmware was released with an unofficial PwnageTool. Now it is time to unlock iPhone 3GS 4.1 firmware. Follow the steps given below to unlock iPhone 3GS 4.1 firmware.
NOTE: You could now use the guide given here instead of this.
2. Launch Cydia.
3. Choose the ” Manage ” tab at the bottom.
4. Choose the ” Sources ” option.
5. Tap the ” Edit ” button and then on the ” Add ” button.
6. Then add the source ” http://repo666.ultrasn0w.com “.
7. After the source is added, search for ” ultrasn0w 1.1-1 ” in Cydia.
8. Install the Ultrasn0w 1.1-1 app to unlock iPhone 3GS 4.1 firmware.
9. Restart your iPhone 3GS.
That’s it! Now you have an unlocked iPhone 3GS running iOS 4.1.