permission denied for schema pg_catalog

I'm sure I'm missing something very simple here...

I've just upgraded from Postgresql-7.3 to 7.4.1.

Whenever I log in as a user without superuser privs I get
ERROR: permission denied for schema pg_catalog

I found a posting somewhere that stated that a lot of defaults changed
in 7.4 for security reasons, but I cannot seem to find out exactly
what changed, and I'm not too keen on just granting ALL to everything
for everyone.

It seems to me that if I use the create_user utility (or indeed just
CREATE USER), I end up with users that cannot really log in and do
anything useful.

Could someone point me in a direction where I can find some
information on what settings I need to change in order to have
"normal" users being able to use a specific database?

Thanks,
Thomas
--
Thomas Bjorn Andersen
+++ATH