iPhone Dev team updates the Redsn0w to hacktivate the iPhone 3G and iPod touch which are updated to newly launched iOS 4. This version not only hacktivates the device but also jailbreak its on iOS 4.
It’s still a beta, so you’ll need to let Cydia reorganize, reload, and update after using redsn0w. If you want to jailbreak your iPhone 3GS, iPod Touch 2G and iPhone 3G running on iOS 4, read the complete instructions here.
In short if you want to hacktivate and jailbreak your iPhone 3G and iPod touch 2G, use this updated Redsn0w 0.9.5 beta 5-3 and if you want to jailbreak your iPhone 3GS with updated iOS 4, try the previous Redsnow 0.9.5 beta 5 which can also be used to enable the multitasking in iPhone 3G and iPod Touch 2G.
At last, if you have not upgraded your iDevice to latest iOs 4, read our 5 steps guide.
Direct Download Links of Redsn0w for both Windows and Mac:
Get the latest version from here: (Updated: 0.9.5b5-5) Another Redsn0w Update 0.9.5b5-4 to Resolve the iBooks/MMS/APN Issues
Update 1: If you face iBooks issues after jailbreaking with this version of Redsn0w, you can run (no need to jailbreak again) the new Redsn0w 0.9.5 b5-4 version to resolve issues.