samba - Nov 2004 - Win SBS 2003 ADS and samba 3.0.8 authentication problem for 11th user

Hi,
I'm running samba 3.0.8 on SuSE 9.0 (heimdal 0.6-161) as a ADS member server
in a Windows SBS 2003 Domain (with 15 client access licences).
My problem is, that every morning, when people login the eleventh user
cannot connect to the samba shares.
After restarting nmb, smb and winbind, they can.

The log file for the client pc shows following error:

...
[2004/11/18 08:56:55, 1] smbd/sesssetup.c:reply_spnego_kerberos(265)
  make_server_info_from_pw failed!
[2004/11/18 08:56:55, 1] smbd/sesssetup.c:reply_spnego_kerberos(265)
  make_server_info_from_pw failed!
...

Now I reboot nmb, smb and winbind...

...
[2004/11/18 09:11:33, 1] smbd/service.c:make_connection_snum(648)
  zchwws12 (192.168.50.112) connect to service Daten initially as user
DOMAIN+username (uid=10021, gid=10000) (pid 7047)
[2004/11/18 09:11:33, 1] smbd/service.c:make_connection_snum(648)
  zchwws12 (192.168.50.112) connect to service Daten initially as user
DOMAIN+username (uid=10021, gid=10000) (pid 7047)
[2004/11/18 09:12:45, 1] smbd/service.c:close_cnum(836)
  zchwws12 (192.168.50.112) closed connection to service Daten
...

Connection works.

Does anyone know, what's wrong?
Thanks for help!