newbie question about PHP

i am trying to connect to a database using webpages with embedded php3.0

postmaster is running with the -i option
the database is running with the -u option
the web user is nobody, and user nobody has select privileges on
the given database.
from the shell, i can access the database as user nobody
$ psql -u mydatabase
Username: nobody
Password: xxxx
mydatabase=>
---------------
<?PHP
 $conn = pg_Connect("localhost", "5432", "user=nobody,password=demo",
"", "grocery");
 if (!$conn) {
   echo "An error occurred.\n";
   exit;
 }
....
?>

this is what resulting page says:

Warning: Unable to connect to PostgresSQL server: User authentication
failed in
        /home1/s/statsol/public_html/test/test.phtml on line 21
                         An error occurred.

my user=,password= is obviously a hack, i am just looking for how to
specify it for the pgoptions part of the pg_connect; help with the
syntax would be much appreciated.

thanks,
steve doliov