[Samba] Can't join domain

[Chris St. Pierre]

I've got a Windows XP box that's unable to join my Samba (3.0.20)
domain.  We've got about 400 other computers, mostly WinXP, that have
joined the domain quite successfully.  I'm not sure when the most
recent one joined, though, but I'm reasonably sure nothing has changed
since then.  The Samba log gives the following when I try to the
computer to the domain:

[2006/02/28 15:33:02, 2] passdb/pdb_ldap.c:init_sam_from_ldap(499)
  init_sam_from_ldap: Entry found for user: stpierre
[2006/02/28 15:33:02, 2] passdb/pdb_ldap.c:init_group_from_ldap(2001)
  init_group_from_ldap: Entry found for group: 1004
[2006/02/28 15:33:02, 2] auth/auth.c:check_ntlm_password(307)
  check_ntlm_password:  authentication for user [stpierre] ->
  [stpierre] -> [stpierre] succeeded
[2006/02/28 15:33:02, 1] smbd/ipc.c:api_fd_reply(290)
  api_fd_reply: INVALID PIPE HANDLE: 739d
[2006/02/28 15:33:03, 2] smbd/server.c:exit_server(608)
  Closing connections
Trust account for mrlc-3$ added with uid 1005 and rid 3010

As you can see, it goes ahead and creates the trust account in LDAP
anyway, despite the PIPE HANDLE message.  (We're using a custom LDAP
trust account script.)  Due to some recent LDAP problems, it's taking
about two minutes to add the machine; could the operation be timing
out?  Any other ideas what might be happening?  Thanks!

Chris St. Pierre
Unix Systems Administrator
Nebraska Wesleyan University