Latest 2g jailbreak / unlock / software

[waveslider]

Hi
I'm currently have an early 2g iphone running 3.0 software,jailbroken & unlocked using redsnow.

Could I just update to 3.1.3 via itunes or will I need to jailbreak / unlock again?

I would like to update to all the latest software in order to sell prior to the new one coming out soon.

Your help (& any links) is appreciated

 

[smashedagainst]

I'm about to do exactly that for a friend's 1st gen iPhone... check out these 2 links:
http://www.jailbreakmatrix.com/
http://modmyi.com/guides/?p=3019/
http://www.redmondpie.com/jailbreak-iphone-os-3.1.3-firmware-with-redsn0w-0.9.4/
http://www.poorlad.com/iCommunity/

I'm feeling pretty confident having read those pages.