Changing DHCP Vedor code in Windows?

Anyone know how to change the default DHCP vendor code in Windows from "MSFT 5.0" to something else? So far, I can't find it in the registry. I'm trying to create a tool for Windows against OS fingerprinting (OSfuscate):

http://www.irongeek.com/i.php?page=s...etection-tools

I've got some success on TCP level stuff, but if the scanner is on the same LAN and it sees a DHCP request the vendor code gives it away. I know it's sort of a parlor trick security wise, but I think it's sort of cool. I'm testing against NetworkMiner that uses the Fingerbanck/Satori fingerprints.