You can use this redsn0w from June to jailbreak 4.0.2 on iPhone3G and iPod2G(non-MC version). Just point it at the 4.0 IPSW (the public one, not the developer GM one). (Yes – point it at the 4.0 IPSW even though you’re at 4.0.2).
This will also hacktivate your iPhone3G at 4.0.2 if you haven’t already been activated by iTunes. Install ultrasn0w if you need a carrier unlock (and in the USA, remember to turn off 3G mode in Settings>General>Network).
- iOS 4.0
- redsn0w 0.9.5b5-5 for Mac
- redsn0w 0.9.5b5-5 for Windows