samba - Oct 2003 - Can't get view samba 3.0 server via winXP, using domain security

I'm sure I'm probably making a common beginner mistake here somewhere,
but I'm stumped.  The facts:

1.  Running samba 3.0.0-2 on rh 7.2.  Trying to access shares on the
Linux box from a WinXP box.  

2. From my linux box, "smbclient //mybox/tmp" connects fine.  I can
see
//mybox in Windows Server Manger, but not via net view or Network
Neighborhood  on the XP box. If I try to access the properties via
Server Manager or get to the server via \\mybox, I get an System Error 5
- Access Denied.  I've verified that firewalling is not an issue,
because the same results happen even if I turn iptables off completely.

3.  log.xpclient file is returning the following error everytime I try
to connect from the XP client:
 [2003/10/06 09:36:08, 0]
auth/auth_util.c:make_server_info_info3(1017)
  make_server_info_info3: pdb_init_sam failed!

    log.smbd and log.nbmd show normal starts and restarts, no errors,
no access denies, so I'm pretty sure that hosts allow in the smb.conf is
not a problem.

4. here's my smb.conf file:

[global]
   workgroup = MYDOMAIN 
   netbios name = MYBOX
  server string = Samba %v on (%L)
   hosts allow = 10.13.   127.
   log file = /var/log/samba/log.%m
   max log size = 50
   security = domain 
   password server = *
  encrypt passwords = yes
  smb passwd file = /etc/samba/smbpasswd
   socket options = TCP_NODELAY SO_RCVBUF=8192 SO_SNDBUF=8192
   wins server = 10.13.1.223

#============================ Share Definitions
=============================[tmp]
   comment = Temporary file space
   path = /tmp
   read only = no
   public = yes
   browseable = yes


What am I missing?  Oh, and one of the first things I did was
successfully joined mybox to the domain w/ the net join command.   And
I've tried specifying the PDC and BDC's instead of using the
"*" for
password server.

~~~Nicoya...