Hi
The MSDE gets installed when you install the UCCX software, by default.
You need to have the windows 2003 from Cisco. The main difference is the Windows directory, which is "Windows" in windows 2003 generic install and "winnt" in the Cisco customized windows 2003 CD.
You can find the details for the customization you need to tweak using the generic windows 2003 by searching Netpro, since this has already been posted earlier.