Apple announced the latest upgrade to iPhone OS 3.1 – firmware version 3.1.2 early last week and if you are waiting to jailbreak iPhone OS 3.1.2, the sad news is that the iPhone Dev team is yet to release the Pwnage and redsn0w tools. But the good news is that, if you are waiting to jailbreak your iPhone, GeoHot has just released BlackRa1n, which will allow Windows users to jailbreak their iPhone with OS 3.1.2.
Jailbreak iPhone 3.1.2 OS with Blackrain
Warning: The current update of Blackra1n only supports iPhone OS 3.1.2, do NOT use this tool if you are using an earlier version of iPhone OS. We have unconfirmed reports that BlackRa1n supports iPhone OS 3.1 as well, but we are not sure.
Also, do not upgrade to 3.1.2 using iTunes if you want to keep your unlock. Baseband cannot be downgraded.
Download Blackra1n for iPhone/iPod Touch
You can download BlackRa1n to jailbreak iPhone and iPod Touch OS 3.1.2:
Once downloaded, make sure to update your iTunes to the latest version.
Update: Jailbreak iPhone 3g/3GS with iPhone OS 3.1.3 with Sn0wbreeze