There is some good news for iPhone 3G (if you don’t care about unlocking), iPhone 2G and iPod Touch 1G users.
iPhone Dev Team who had issued a warning that users wanting to jailbreak and/or unlock their iPhone should not upgrade to iPhone OS 3.1.3 is reporting that RedSn0w 0.9.2, their latest cross-platform jailbreaking, unlocking and customization tool can jailbreak iPhone OS 3.1.3.
We recommend that you read the post very carefully before
Dev Team is reporting on their blog:
[Don’t go near this if you have 3GS, newer ipt2G, or any ipt3G] Thanks to daring experimenters in the comments, we can confirm that yesterday’s redsn0w works for today’s 3.1.3 update for iPhone 2G. Just point it at the 3.1.2 iPhone 2G IPSW after doing update or restore to 3.1.3. So far we’ve only confirmed this for iPhone 2G. (Note that if this does work for iPhone 3G too, you can *only* use it if you don’t care about the unlock.)
[Don’t go near this if you have 3GS, newer ipt2G, or any ipt3G] Can confirm that this method works for iPhone 3G and iPod touch 1G too. Don’t do it for iPhone 3G if you need an unlock though (really, don’t!). For older iPod touch 2G, we’ll need a small (1-character) change in redsn0w source.
So the iPhone OS 3.1.3 update is safe for iPhone 2G and iPod Touch 1G users. It is also safe for iPhone 3G users who don't care about unlocking. Users who have iPhone 3GS, iPod Touch 3G and newer iPod Touch 2G should AVOID upgrading to iPhone OS 3.1.3.
Please remember hacking your iPhone could void its warranty. So please proceed with caution and at your own risk and don’t forget to take a backup of your iPhone (refer to this post for more details).
If you have an iPhone 2G, iPhone 3G (but don’t care about jailbreaking) or iPod Touch 1g and plan to try RedSn0w (download details available in this post), please let us know how it goes in the comments.[via Dev Team’s blog]