The iPhone Dev-Team has successfully completed
the upgrade of a jailbroken iPhone 3GS from 3.0 to 3.1 without losing the jailbreak.
CPICH confirmed the news from his twitter account.
This means that we will likely see an update to PwnageTool which will add support for creating a custom ipsw that will be used to upgrade your iPhone 3GS.
We will update our tutorials as soon as it becomes available. In the meanwhile check out the screenshots below from CPICH.
Original source
