The official ultrasn0w unlock has been released by iPhone Dev Team for iPhone 3GS, with older bootrom running 04.26.08 baseband on iOS 4.0 (formerly iPhone OS 4).
For those of you who preserved their baseband by jailbreaking iPhone 3GS on iOS 4 using PwnageTool can now unlock, provided that your phone is running the older 04.26.08 baseband.
Note: As mentioned above, this is strictly for iPhone 3GS on iOS 4.0, with 04.26.08 baseband only.
If you are on 05.12.01 baseband, you will need to wait for the end of June to get your phone unlocked.
Guide: How to Unlock iPhone 3GS 05.11.07 Baseband on iOS 4:
Step 2: Once you are done with the jailbreak, you can now unlock your iPhone 3GS running custom iOS 4.0 firmware by using ultrasn0w 0.92.1 from Cydia. To do this:
- Start “Cydia” on your iPhone.
- Touch on “Manage” tab on the bottom.
- Now touch on “Sources” as seen in the screenshot below:
- Touch on “Edit” and then on “Add”. You will be prompted to enter a url source as seen in the screenshot below. Type “http://ios4.ultrasn0w.org” and touch on “Add Source”.
Cydia will now automatically update your sources by following a series of automated steps.
- After installation is completed. Search for “ultrasn0w 0.92” in Cydia and install this application. This app will automatically unlock your iPhone 3GS so that you can use it with any carrier.
Step 3: Now simply restart your iPhone and voila! you should now have a fully unlocked iPhone 3GS, on iOS 4.