Here’s an interesting problem: After you apply Windows 2003 SP1, the new security settings prevent running HTA files from a network share. So this means if you download the Exdeploy pack and dump it into a network share, it won’t work properly on a W2k3 SP1 server.
The workaround, of course, is to put the files locally on the W2k3 SP1 server.
Seems to me that people most affected by this should be those who are doing cross-site mailbox moves, since anyone doing a regular in-place upgrade from Exchange 2000–>2003 wouldn’t yet be running the server on Windows 2003 SP1.
See KB.897340 for more info.