I have not been able to use oemscan in this way, but Severach on MSFN was recommending "XP License Changer" for post use:http://board.defcon5.biz/viewtopic.php?f=5&t=720
I looked it over and didnt really get it, so I just bookmarked it and figured I would come back to it one day. Never have had time. It was last updated in 2008 though
I also bookmarked this one, but havent had a chance to play with it at all. http://forums.mydigitallife.info/threads/6077-VLK-and-OEMBIOS-changer
I would love to find a post solution, to use along with oemscan. I have too many computers where oemscan mis-guesses the correct oem.