Network password?

[gmabbutt at mts.net]

Hi, I've just been trying to set up Samba 2.0.3 on a Red Hat 6
box using the included RPM.  I've looked through the faq and the
mail archives and can't find what I'm looking for.  Here goes:
at the moment it sort of works, in that the box itself is
viewable from Network Neighborhood.  However, if you double
click on the server, a dialog box comes up saying:

Enter Network Password: You must supply a password to make this
connection
Resource: \\QSCLINUX\IPC$
Password:

The Linux root password doesn't work.

Which is odd because I thought I had fixed that in smb.conf. 
Any ideas?  I ran smbclient -L QSCLINUX earlier and got a
description of the smb network, after hitting enter with nothing
for the password.  However, now when I run smbclient -L
QSCLINUX, I get a message saying "protocol negotiation failed". 
Help!