How do I clean out my NT server?

Network: 1 server, NT 4.0, 22 workstations, win98. 15 email accounts for sales staff.

Was hit by klez virus among others recently. I have installed Norton on the win98 machines and sweep and clean occassionally. However, during the time the viruswas active, it wrote files to the server. And it seems that occassionally one of the workstations will start thrashing the hard drive, and next thing you know, more corrupted files on the server.

Is there a way to sweep a NT4.0 server for these viruses? Or to clean up the infected files? Norton won’t go on NT4.0. Will the FixKlez program work on NT?

Any ideas would be appreciated.