postgres user authentification

I have a light pg_hba.conf file:

local        all                                           trust
host         all         127.0.0.1     255.255.255.255     trust

Which doesn't look so bad, just because at the server there are few accounts,
and all from admins. But is there a way to make it imposible to do this:

webunl=> \c - postgres
You are now connected as new user postgres.
webunl=#

I mean, I don't want others to simply do a \c - postgres and thats all. Is it
posible without changing the trust for a password?

Saludos... :-)

--
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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