[OpenAFS] klog: "Unable to authenticate to AFS because user doesn't exist."

[Paul Wachendorf]

Hallo,
since a few days I cannot get a admin tokens via klog:

klog admin@impetus.uni-koeln.de
Password:
Unable to authenticate to AFS because user doesn't exist.

the user admin exists:

 pts examine admin -cell impetus.uni-koeln.de
libprot: no such entry Could not get afs tokens, running unauthenticated.
Name: admin, id: 1, owner: system:administrators, creator: anonymous,
  membership: 1, flags: S----, group quota: unlimited.

kas examine admin -admin admin -cell impetus.uni-koeln.de
Administrator's (admin) Password:

User data for admin (ADMIN)
  key (1) cksum is <chksum>, last cpw: Fri Aug 10 08:57:38 2007
  password will never expire.
  An unlimited number of unsuccessful authentications is permitted.
  entry never expires.  Max ticket lifetime 25.00 hours.
  last mod on Wed May 16 17:08:55 2007 by <none>
  permit password reuse

and at last kaserver seems to check the passwort too, because when i 
type in a wrong one:

 klog admin
Password:
Unable to authenticate to AFS because password was incorrect.

This happens both at server and any client.

Has anyone a idea whats going wrong?

Thanks and sorry for my bad english,

Paul Wachendorf