CIFS / SDIDIAG error -626

Hello.

This is my first try to install CIFS on NW 6.5 (SP8 with eDirectory
8.7.3.10, single server).
I created a new (universal) Password policy in the user "Benutzer"
container, but the SDIDIAG check fails.

------------------------------------------------------------------------
SDIDIAG> check -v >> sys:system\sdidiag.txt -n OU=Benutzer.O=XX
*** [Key Consistency Check - BEGIN] ***
[Checking SDI Domain]
SDI Check Domain Configuration...
SDI Domain Key Server .XX.XX.MU.
- Configuration is good.
*** SDI Check Domain Configuration is [GOOD]
SDI Check Domain Keys...
SDI Domain Key Server .XX.XX.MU.
- Keys are good.
*** SDI Check Domain Keys are [GOOD]

[Checking SDI Domain: GOOD]

[Checking Servers]
*** Checking container .OU=Benutzer.O=XX. ...
- Could not be checked. (error = -626)

Servers Hosting .OU=Benutzer.O=XX. Have Key Problems.
Recommendations:
- One or more servers could not be checked
because of errors. You should check that these
servers are operational and may be accessed;
otherwise, you may have problems using services
from these servers.

- You must upgrade at least one server hosting a
writable replica of this container to NetWare 6.5
or to eDirectory 87.1


[Checking Servers: PROBLEMS]

*** THERE ARE PROBLEMS! ***

*** [Key Consistency Check - END] ***
Error on command = -626
------------------------------------------------------------------------
I used sdiag also with TID 3455150, but I cannot see any errors here.
When I use network neigborhood I see the server, but cannot login.

Thanks for help,
Michael