samba - Jan 2005 - Strange message log from ldapsam_search_one_group()

Hello,

I've a Debian 3.1 box with Samba 3.0.9 acting as a PDC with OpenLDAP
2.1.30, libdbd-4.2.52, smbldap-tools 0.8.5, libnss-ldap version 220-1.

Sometimes I get a burst of 20-30 messages with the same timestamp
like these:

[2005/01/30 19:17:43, 0, pid=13107, effective(0, 0), real(0, 0)]
passdb/pdb_ldap.c:ldapsam_search_one_group(1982)
  ldapsam_search_one_group: Problem during the LDAP search: LDAP error: (No such
object)

It seems that samba is looking the group of the user having id=0 and
gid=0, which corresponds to the Unix user root.
In te LDAP DB the user administrator has the following id:

drake:~# id administrator
uid=0(root) gid=512(Domain Admins) groups=0(root)

Please note that the disk shares have almost all the files owned by id=root and
gid="Domain Users" and have permission to 777 for directories and
666 for files (everyone can write everything :). 
May this be a problem? 
Do I have to remap the root Unix user to the user Administrator in some
way?

Besides, sometimes there is another suspicous message like this:

[2005/01/28 10:54:41, 0, pid=9760, effective(0, 0), real(0, 0)]
passdb/pdb_ldap.c:ldapsam_search_one _group(1982)
 ldapsam_search_one_group: Problem during the LDAP search: LDAP error: (No such
object)
[2005/01/28 10:54:41, 0, pid=9760, effective(1109, 513), real(1109, 0)]
rpc_server/srv_util.c:get_alias_user_groups(206)
 get_alias_user_groups: gid of user emanuele doesn't exist. Check your
/etc/passwd and /etc/group files

But if I do for the user "emanuele" the following:
drake:~# id emanuele
uid=1109(emanuele) gid=513(Domain Users) groups=513(Domain Users)

Obviously it is not in /etc/passwd and /etc/group because it is stored
in the LDAP Backend.

Since "syslog = 0" I'm asking if these messages are
"normal" or if there
is something wrong with my setup. Apparently there are no other anomalies.

TIA,
Luca