Upgrading to iPhone 3G to iPhone OS 3.1.2, with keeping the baseband at 04.26

I think this is my first post on iPhone ( barring the rant). o_O. Surprising, since I purchased the iPhone from eBay close to a year ago. Anyhow, being the computer freak enthusiast that I am,  I keep a track of most of the latest software that appears on the tech scene.  I generally have a zero-day update policy – any new version/update that arrives for a software I generally