Lucky you!
From the symantec knowledgebase:
If the parent server is Windows NT/2000/XP, then copy the Grc.dat file from the VPHOME shared folder on the parent server. By default, the shared folder points to <OS drive>:\Program Files\SAV on the parent server.
For Windows 2000 or XP clients, the Grc.dat file must be copied to the following folder:
<OS Drive>:\Documents and Settings\All Users\Application Data\Symantec\Norton AntiVirus Corporate Edition\7.5
You also want to be sure you designated your server as the parent server.
Hope this helps. I just learned more than I ever wanted to know about Corporate Edition due to a faulty installation on the server (NT4.0 SP6).
Clients are happy, server is still marginal.