10.3 Server Refreshing directory

We have got a problem with a new server installation. The Server is a G5 with OSX Server 10.3.2, serving volumes from two Scsi-Scsi-Raidsystems (1,2 TB) by AFP. The Clients (maybe 20) have 9.2 installed. The problem is that the content of a window, showing the directory of any volume on the server, isn't refreshed automatically. That means you openend a window on the client showing a directory of the server and anybody else copies a file from his client to the server. This filoe isn't shown on your client (or on the server) until the is closed/reopened or a suddirectory is closed/opened. The former server (G4, 10.2) didn't have that problem. Any hints?