problems with pg_dump... with postmaster really

I have found that the postmaster is dying very offen lattly, and yesterday I
got this error on a pg_dumpall:

connected to template1...
dumping database "horde"...
dumping database "lismarch"...
pg_dump: NOTICE:  Message from PostgreSQL backend:
        The Postmaster has informed me that some other backend
        died abnormally and possibly corrupted shared memory.
        I have rolled back the current transaction and am
        going to terminate your database system connection and exit.
        Please reconnect to the database system and repeat your query.
pg_dump: query to obtain list of operators failed: server closed the
connection unexpectedly
        This probably means the server terminated abnormally
        before or while processing the request.
pg_dump failed on lismarch, exiting


I got these kind of errors in normal conections too. Any idea?

--
Porqué usar una base de datos relacional cualquiera,
si podés usar PostgreSQL?
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Martín Marqués                  |        mmarques@unl.edu.ar
Programador, Administrador, DBA |       Centro de Telematica
                       Universidad Nacional
                            del Litoral
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