pg_hba.conf file

I'm currently working on a proyect that has Postgres as the database storage
server, and PHP-4.0.4pl1 as the language to use in comunication with the users.
What I can't get to understand is how PHP comunicates with the database, so that
I can set the correct hba.conf enteries.
PHP will be on the same server as Postgres is, and the pg_hba.conf file contains
this, which I'm not sure is a good configuration:

local all trust
host all 127.0.0.1 255.255.255.255 password
host all 168.96.132.31 255.255.255.0 password
host all 170.210.8.31 255.255.255.0 password

What do you people hear think of this? I'm consurned about the local enterie,
but when I put password instead of trust, I can't login with PHP to the
database.
Any thoughts?

Saludos... ;-)

System Administration: It's a dirty job,
but someone told I had to do it.
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Martín Marqués email: martin(at)math(dot)unl(dot)edu(dot)ar
Santa Fe - Argentina http://math.unl.edu.ar/~martin/
Administrador de sistemas en math.unl.edu.ar
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