Open Database with Pgaccess

I  know, it's a basic question (sory) but i didn't find doc.
I'm working with Postgres6.3.2 and pgacess0.9 (with Linux Redhat 5.2 or
Debian 2.0)
I've done :
      * on  root account
            * su postgres
            * createuser Dizzy (this user already exists (users-group))
            * that's was Ok

      * on Dizzy account
          *createdb KADOCKDB
          *psql KADOCKDB
          *create table client (nom_client char(20) not null primary
key);
          And all seems OK

But with Pgaccess, I can't open database
         Host          localhost
         Port            5432           (???)
         Database   KADOCKDB
         Username Dizzy
          Password (Dizzy-Password)

Error connecting database
Is postmaster running (Yes )
and accepting TCP.IP connection at 'localhost' on port '5432'  (I don't
know)

Thanks for you answer

( Where can i find documentation and script about
Apache->CGI(Perl)->Postgres ?)
(I've downloaded DBI an DBD)