That's a good question. The downloads of XP and VX that we provide aren't exactly free, since you only have a 30 day demo period before you have to buy the program. 2k3 is set up the same way, but it was never officially translated into English. What people download for free I believe is a fan translation of the program. This is technically an illegal distribution, but I doubt Enterbrain cares at all. They can't expect an English audience to buy a program in a language they don't understand, it's outdated, and it does help promote the newer versions that are translated.
Mind you, I could be completely wrong. I mostly use XP, not 2k3.