Files disappear when copied to server

We are on a large network that is Windows based (the network is Novell, I think). We have two offices that are on different subnets and are running Panther Server on a 1.25GHz G4 (all updates applied as of 5/28/04). Our clients are mixed OS 9 and OS X (10.3.4 except one 10.2.8). The problem is that when a user copies a file into a directory through the Finder, the 10.2.8 client cannot see the file. I have tried forcing updated permissions on the file through the Finder as well as the Terminal. This also happened yesterday on a 10.3.4 client when a folder that I was moving a lot of stuff into suddenly disappeared. The folder or file is always there when looked at on the server, but the client cannot see it. A reboot of the server usually fixes this. Has anyone seen this behavior and does anyone know of a fix? A search of both this site and Apple support has produced nothing. Thanks.