I guess those are ms nameservers pointing to http://www.savvis.net/ hosted servers, so that is explainable, what about not upgrading to 2003?
For the most part MS always runs the latest Gold releases or even the new betas on their servers. But like many of us they probably have those few computers that are sitting in a corner somewhere, maybe not even used. Or even more likely, legacy DNS entries
pointing to legacy boxes. I tried a couple of those 2K entries and most redirected to new addresses, the rest just gave 400 level errors.