Damaged table "pg_access"

Hello all,

when I try to access the system-table "pg_class", I get the following
error:

zeda=# select * from pg_class;
NOTICE:  get_groname: group 1 not found
pqReadData() -- backend closed the channel unexpectedly.       This probably means the backend terminated abnormally
  before or while processing the request.
 
The connection to the server was lost. Attempting reset: Failed.
!#

What happened? Is there any way to repare the damaged table?

Thanks in advance for all of you, who spend their valuable time!

Best regards, Jens

=============================================
Jens Hartwig
---------------------------------------------
debis Systemhaus GEI mbH
10875 Berlin
Tel.     : +49 (0)30 2554-3282
Fax      : +49 (0)30 2554-3187
Mobil    : +49 (0)170 167-2648
E-Mail   : jhartwig@debis.com
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