Help with PostgreSQL Access

Apologies if this is an FAQ, but I haven't been able to find an answer
anywhere.

I have created a database using psql, created a couple of tables and populated
them, following the tutorial on the PostrgreSQL site.  I can view the
contents of the tables using SELECT so the database exists and contains data.

My query is concerning PostgreSQL Access.  When I open it none of the icons
work and I assume that I have to use Database/Open to tell it the name of my
database.  The Host is shown as localhost and the Port is set to 5432.  No
matter what I enter in the other icons I get the following error message:

Connection to database failed
could not connect to server: Connection refused
Is the server running on host localhost and
accepting TCP/IP connections on port 5432?

I have tried this on 2 machines running PostgreSQL 7.2.2-1 on Mandrake Linux
9.0.

Any suggestion would be gratefully received.

Andrew Tuson