Do wonder though if Windows Safari is a special version? Internet Explorer has a special version to run on apple computers!
You mean IE 5 for the Mac? While it wasn't the same as IE 5.x for Windows, Safari for Windows is the same as the Mac version. Subtle differences may occur for various reasons, including font differences because the OS's don't have all the same fonts, and they are smoothed (or not) differently.
You can always check your pages in otherwise unavailable browsers using browsershots.org or a similar service.