iH8snow has released the latest version of his sn0wbreeze pwnage tool for windows along with updates to several other tools to help iPhone 3G[s] and iPod touch 3G owners preserve a 3.1.2 jailbreak when shift-updating to a sn0wbreeze-generated iOS4 custom firmware.

The only requirement for new bootrom devices is that they must already be on or able to downgrade to iOS 3.1.2. Not a major issue for iPod touch 3G 8GB owners as we all know the hardware wasn’t updated in these devices and they can downgrade using an iPod touch 2G 3.1.2 firmware file. However, owners of MC model iPod touch 3G 32/64GB and new bootrom iPhone 3G[s] owners will need to have 3.1.2 SHSH blobs saved on Saurik’s server or locally in order to get back to 3.1.2. 

iH8snow’s method isn’t easy to implement and there’s a lot of members having issues but it does work. So if you’re really desperate for a jailbreak and can’t wait for comex’s  forthcoming all encompassing  iOS4  userland   jailbreak then have a go and let us know how you get on in the comments here.