Pwnage Tool 4.2 to Jailbreak iOS 4.3.1 for iPhone 3GS all basebands
It time for iPhone 3GS older baseband and New Baseband to be Jailbreak on IOS 4.3.1 with Pwnage Tool 4.2. Previously Pwnaga tool 4.2 jailbreak IOS 4.3.1 on iPhone 4 and it was done with ipad jailbreak on iOS 4.3.1 but this time Old Baseband and New Baseband iPhone 3GS Jailbreak comes with Pwnage tool 4.2 for iOS 4.3.1
The unlock for iOS 4.3.1 is still not here so if you need unlock iPhone 3GS and you have updated to iOS 4.3.1, here is the post of Downgrade IOS 4.3.1 to Older Firmware and Get it Unlock.
if you still do not want to Unlock your device you can follow the procedure mentioned in the recent post of Pwnage Tool 4.2 to Jailbreak iPhone IOS 4.3.1, which is similar for the iPhone 3GS IOS 4.3.1 Jailbreak with Pwnage tool 4.2.