ummhh.. where did you find it? I googled a while but wasn't able to find.. can u share a link?
Anyway i talked to the prey's developper teamleader and seems that prey is actually developped only for linux and os x. As you can see from the official site prey's linux and osx versions are up to date, the windows version isn't. There was a windows developper, but he abandoned the project. Anyway the source code is public available.. if there's a window developper available that could share his efforts for this project just send a mail here at this googlegroup. (couldn't it be better to open a prey googlegroup?)