A few days back I released a Â guide for jailbreaking iPhone 3G/3GS and iPod Touch 2G/3G 3.1.2 firmware with Blackra1n. But it worked only in Windows and not in Mac OS X. But now the Mac OS X version of Blackra1n has been released and here is a guide to jailbreak iPhone 3G/3GS and iPod Touch 2G/3G in Mac OS X.
NOTE: Those who don’t care about changing your SIM should only do this. If you want to do that then you should jailbreak your iPhone with PwnageTool 3.1.4.