George Hotz a.k.a GeoHot was the first one to release BlackRa1n tool to jailbreak iPhone OS 3.1.2. The initial version had many issues, and now most of them have been fixed in the latest version – Blackra1n RC2.
Blackra1n RC2 can jailbreak all iPhone’s (2G/3G/3GS) and iPod touches (1G/2G/3G) running iPhone firmware 3.1.2. It can also tethered jailbreak 3.1 OOTB iPod touch 8GB and all the new iPhone 3GS’s. In case you have already used Blackra1n then there is no need to rerun Blackra1n rc2.
Features of Blackra1n RC2
* Fixed all issues that you might had when jailbreaking iPhone 3G with Blackra1n RC1.
* Tethered jailbreak for 3.1 OOTB iPod touch 8GB and all the new iPhone 3GS’s.
* Fixed Icy issues.
* Works on both Windows and Mac.