Geohot has released his BlackSn0w utility. BlackSn0w is an unlock for the iPhone 3G and iPhone 3GS. It supports the latest firmware 3.1 and 3.1.2 with baseband 05.11.07 and enables official tethering. Available for both Windows and Mac.
Here is a quick tutorial:
If you havn’t done the jailbreak: go to
If your device is already jailbroken – run Cydia, add repository blackra1n.com and install blacksn0w. That’s it!
The latest version of blackra1n is RC3. It now has hacktivation support, 15 second speed improvement, Tiger+PPC support.
PS: If you just bought a new iPhone 3GS or have one that was made recently (approximately after 40th week after iPhone 3GS release): your device has a new BootROM. Unfortunately it is impossible to run regular jailbreak with this new BootROM. There is a sloution – tethered jailbreak. Everything including unlock will work fine. However every time you restart your iPhone, you need to plug it to a computer with blackra1n installed.