Problem with pg_user (somewhat urgent)

Hi,

We have a PostgreSQL 7.3.4 cluster which is used by several
customers.  Every customer has his own database.  I have
revoked SELECT access on pg_user from the customers, because
they should not be able to see which other customers exist
on the cluster.

However, now the customers cannot use pg_dump anymore:
<QUOTE>
pg_dump: SQL command failed
pg_dump: Error message from server: ERROR:  pg_user: permission denied
pg_dump: The command was: select (select usename from pg_user where usesysid = datdba) as dba, encoding, datpath from
pg_databasewhere datname = 'antonhurz' 
</QUOTE>

Is there any way to resolve the problem?

If I understand things right, every DB has its own copy of
pg_user, right?  Then I _should_ be able to delete all other
users from pg_user, except the owner of the DB (and possibly
the pgsql superuser), then grant SELECT access back to
everyone.  Repeat that step for every database.
Would that work?  I'm a bit reluctant to just try it,
because I don't want to break anything and make matters
worse.

Any help would be greatly appreciated!  Thanks in advance!

Regards
   Oliver

--
Oliver Fromme, secnetix GmbH & Co KG, Oettingenstr. 2, 80538 München
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