Netware problems seeing another server

We have a Netware 5.1 server, Netware 5.0 server, NT 4.0 server with NDS for NT.
The Netware server’s are always reporting the following error:
Unable to communicate with server .App-Svr.treename

The server that’s it cant communicate with is the NT server with NDS for NT on it. When I run a dstrace on the netware server I see some -625 error’s on it. So far, all server’s havent given us any problems. Is this just a cosmetic error?

Any ideas what I can do to get rid of this error?

Thanks

Eric