iphone jailbreaking for iphone 3gs which has been updated to 4.0 version

Question

I have a question How to remove latest iphone 4.0 version from iphone 3GS(4.0 has been updated on 3GS unknowingly)? Is it can be done through jailbreaking?Please help me in this.

Thanks,

Answer 1

Here's some guides for downgrading from 4.0 on a 3G[S]

http://lifehacker.com/5572003/how-to-downgrade-your-iphone-3g%5Bs%5D-from-ios-4-to-ios-313

http://www.redmondpie.com/downgrade-ios-4-iphone-3gs-3g-and-ipod-touch-to-iphone-3.1.3-3.1.2-how-to-guide/