Samba Client Usually Can't Attach to Samba Server

[Bruce Feist]

ursula is an older RH system (8.x, I think), running Samba server and 
publishing several directories, including /shr, /shr2, /shr3, and others.
janus is a new Fedora 4 system.

Windows 2000 and XP machines on the same network are able to access all 
volumes published by ursula uneventfully.  So is a Macintosh running 
System/X.

janus is usually unable to access the volumes.  I have tried to access 
them using smbclient, mount, and also using Nautilus 2.10.0.  Typically, 
there is a fairly lengthy delay followed by a message indicating that 
not everything could be displayed.  I *think* that only one volume is 
actually accessable.  There is nothing obviously different about it.

I'm using "user" authentication.

What could be causing this?

TIA,
Bruce