iPhone developer @ih8sn0w has just released an updated version of Sn0wbreeze 2.8 for iOS 5 beta 1 jailbreak. This new version of Sn0wbreeze adds support for untethered iOS 5 jailbreak on iPhone 3GS, old bootrom.
You can follow our detailed guide posted here. iOS 5 is currently in Beta and available to registered developers only or registered devices. Apple will launch final version of iOS 5 to public this Fall.
Required Downloads: