Correct configuration to access Postgres 7.3 from remote client?

First, I modified these lines in the postgresql.conf file:
tcpip_socket = true
port = 5432
virtual_host = '20.20.20.4, localhost'

where 20.20.20.4 is the address of the postgres server. Is this needed?

Second, I modified pg_hba.conf and added this line:
host all all 20.20.20.5 255.255.255.0 trust

where 20.20.20.5 is the client machine that I need to access the
database from.

Then I call "pg_ctl reload -D data_directory" to reload the config file
changes.

Then from the client I issue:

pg_dump --host=20.20.20.4 -o mydb > remotedump
pg_dump: [archiver (db)] connection to database "mydb" failed: could not
connect to server: Connection refused
Is the server running on host "10.10.18.53" and accepting
TCP/IP connections on port 5432?

It looks like the server is not configured properly. Does anyone know
what I am missing?

One strange thing is the postmaster.opts file contains the following:

cat postmaster.opts
/usr/bin/postmaster '-i' '-h' '127.0.0.1'

I though it would contain '-h' '20.20.20.4, 127.0.0.1' because of my
virtual_host setting.

Any help would be greatly appreciated.

Lewis Kawecki
E: kawecki_lewis(at)emc(dot)com