Many users of the iPhones, especially the the iPhone3G have not been happy campers post upgrading to the iOS4.

The problems have been numerous ranging from performance issues and system issues. Apple has taken note of this issue an reportedly looking into it.

It is difficult to say how far this fix would alleviate the problems on the iPhone 3G running on the iOS4. Apple seems to(and probably is) be pushing the consumer to change their iPhones every two years. The iPhone4 is out and many users are waiting for it with bated breath.

Lifehacker, a tech site has provided a step by step guide to downgrading the iPhone 3G(S) from iOS4 to iOS 3.1.3. You can view this guide via this link.