[Samba] samba server as dfs host?

[Basil Copeland]

I'm trying to configure a samba server in a Win2K3 domain as a dfs host.

The dfs host part is working: from a win client I can map the dfs root
on the samba server (on FC3 fwiw) and see the link I've created to a
share on a Win2k3 active directory domain controller.  From samba
server, I can smbclient to the share on the Win2k3 DC, and can mount
the share as "-t cifs" (but not "-t smbfs" if that's any clue: this
returns the smb signing error).

For testing purposes I've added "everyone" to the security permissions
for the share on the Win2k3 DC, but that doesn't seem to do anything. 
With the mount "-t cifs" I am prompted for a domain user account and
password.  But trying to get to the share through the dfs link doesn't
even do that (prompt for a user and password).

I suspect that this is a Win2k3 configuration issue, but am hoping
nonetheless that a Samba guru can point me in the right direction.