samba - Mar 2005 - Are "builtin" groups supposed to work with ldap?

This is with 3.0.11 and the idealx smbldap-tools 0.8.7

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# /opt/IDEALX/sbin/smbldap-groupshow 'Domain Admins'
dn: cn=Domain Admins,ou=Groups,dc=wetron,dc=es
objectClass: posixGroup,sambaGroupMapping
gidNumber: 512
cn: Domain Admins
memberUid: Administrator,luca
description: Netbios Domain Administrators
sambaSID: S-1-5-21-1375475485-2168029398-3937786652-512
sambaGroupType: 2
displayName: Domain Admins

# net -U luca rpc group members 'Domain Admins'
Password:
WETRON\Administrator
WETRON\root
WETRON\luca
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Ok, that's good

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# /opt/IDEALX/sbin/smbldap-groupshow 'Administrators'
dn: cn=Administrators,ou=Groups,dc=wetron,dc=es
objectClass: posixGroup,sambaGroupMapping
gidNumber: 544
cn: Administrators
description: Netbios Domain Members can fully administer the 
computer/sambaDomainName
sambaSID: S-1-5-32-544
sambaGroupType: 5
displayName: Administrators
memberUid: luca

# net -U luca rpc group members 'Administrators'
Password:
[2005/03/07 21:06:09, 0] rpc_client/cli_pipe.c:rpc_api_pipe(435)
   cli_pipe: return critical error. Error was Call timed out: server did 
not respond after 10000 milliseconds
Couldn't list alias members
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Not so good. The log is saying:

  [2005/03/07 21:06:14, 0] lib/smbldap.c:smbldap_open(881)
  smbldap_open: cannot access LDAP when not root..


Let's try again as root

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# net -U Administrator rpc group members 'Administrators'
Password:
#
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No error this time, but there's no user in the group (while 
smbldap-groupshow tells I'm in that group).
What am I doing wrong?

Bye.
-- 
Luca