As a guess, it was a guess.
The MSI for Service Pack #2 does make slight adjustments between Home, Pro, and Win2003 Server. Between XP pro and Win 2003 server I have not seen any adjustments, but I did not track this carefully, and we are still talking BETA.
I think that bluejacket read the 'Supported Operating Systems' line as implyinjg only Server Windows 2003. This strickes me as a misprint as well.
Normally you get an exhaustive listing of supported OS versions for a fix, even with installer ability to tell the difference.
cdogg does make a good point: there are a lot of versions of the Service Pack 2 out there. As far as I know the "best" would be the version released as a trial to the MSDN community.
All would be better off asking for help on a specific problem here, then downoading and applying even a legitimate copy of Service Pack #2. The MSDN community gets frequent updates. Your download source does not.
It is not worth playing with. Most MSDN subscribers to not think it is worth playing with at the moment.
Just wait.