Download RedSn0w 0.9.6b5 Jailbreak iOS 4.2.1 and Update Baseband to 06.15.00

The iPhone Dev Team has released Redsn0w 0.9.6b5 to jailbreak iOS 4.2.1 and update baseband to 06.15.00. So, the iPhone 3GS, 3G users with baseband 05.15.04 and 05.14.04 should update their iDevices baseband to 06.15.00 with RedSn0w 0.9.6b5.
RedSn0w 0.9.6b5 is available for Windows and Mac users.

Note: Windows 7 and Vista users should run Redsn0w as Administrator in XP Compatiblity Mode.

Download RedSn0w 0.9.6b5 for Windows

Download RedSn0w 0.9.6b5 for Mac

Download iOS 4.2.1