invalid memory alloc request size

Hi,

my cron job which is dumping the databse fails this night. I got:

pg_dump: ERROR:  invalid memory alloc request size 18446744073709551614
pg_dump: SQL command to dump the contents of table "spieletipps" failed:
PQendcopy() failed.
pg_dump: Error message from server: ERROR:  invalid memory alloc request size
18446744073709551614
pg_dump: The command was: COPY public.spieletipps (tr_kurzname, mg_name,
sp_id, stip_heimtore, stip_gasttore) TO stdout;

I am running
  postgresql-server-8.0.3-1.2
  on SuSE Linux 9.3 (x86-64)

I had this a few days before and decided to use a recent backup. It works fine
for two days only. Maybe my harddisk is broken? Maybe 64-bit is broken? i
have no clue and no idea what do to. i ve searched the archives and found a
recent thread on HACKERS but sorry guys: i dont know how to produce a
backtrace.

select count(*) from spieletipps;
  count
----------
 11612957
(1 Zeile)

works fine. When i do something like this:

$ select * from spieletipps where sp_id > 10000000;

Server beendete die Verbindung unerwartet
        Das heißt wahrscheinlich, daß der Server abnormal beendete
        bevor oder während die Anweisung bearbeitet wurde.
Die Verbindung zum Server wurde verloren.  Versuche Reset: Fehlgeschlagen.

(it means: server closed the connection unexpectedly. ... Try to reset
connection failed.)

Please help me!

kind regards,
janning