Sn0wbreeze 3.1.3 is now available for download which can jailbreak iPhone 2G, 3G and iPhone 3GS (old bootrom only) on iPhone OS 3.1.3. We have already published a detailed guide on how to jailbreak using Sn0wbreeze and unlock using ultrasn0w. Ultrasn0w unlock is for iPhones with baseband 04.26.08 baseband. If you are on 05.11.07 baseband, then you may use Geohot’s blacksn0w unlock which was released last year with blackra1n.
Follow the simple step by step guide below to unlock your iPhone 3G and iPhone 3GS (old bootrom only) on iPhone OS 3.1.3 using blacksn0w. iPhone 2G users should follow the guide posted here (Mac version of the guide here).
How to: Jailbreak iPhone on 3.1.3: Step 1: Follow the guide posted here to jailbreak your iPhone 3G or 3GS using Sn0wbreeze 3.1.3 on iPhone firmware 3.1.3.
How to: Unlock iPhone 3G/3G (old bootrom) on 3.1.3: Step 2: Once you are done with the jailbreak, you can now unlock your iPhone running jailbroken firmware 3.1.3 by using blacksn0w 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://blackra1n.com” 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 “blacksn0w” in Cydia and install this application. This app will automatically unlock your iPhone so that you can use it with any carrier.
Step 3: Now simply restart your iPhone. Voila! You are now running a fully unlocked and jailbroken iPhone on firmware 3.1.3 on your iPhone 3G or 3GS.
UPDATE 1: A working exploit for iPhone 3.1.3 05.12.01 Baseband has been found. More info here.
You can follow me on twitter or join our facebook fanpage to keep yourself updated on all the latest iPhone jailbreaking and unlocking releases.