Pgaccess doesn't connect

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Hello and sorry for my bad english ;-)

I've a lot of problems with my postgreSQL.
I use mandrake linux 9.0 with postgres 7.2.2 and i
eliminated postgres user password...

I logged as postgres user and i created "prova_db" database.
Then i created "indirizzi" table in which i put three addresses.
If i manage my postgres database as postgres user with "psql" command
all works fine.

Problems arrive if i do not log as postgres user but as my usual user (nathanvi).
If i launch pgaccess and try to open my database as in the attached PNG
my system responds in this way:
"Error trying to connect to database 'prova_db' on host localhost
PostgreSQL error message: Connection to database failed
could not connect to server running on host localhost
and accepting TCP/IP connection on port 5432?"

In the same way if i try to connect to database with a PERL script with Pg module
that i've attached as "prova_db_connessione2.pl" and i try to add a record, it responds:
Variabile result: PG_results=SCALAR(0x804c130)

What can i do?
Please help me....

PS Obviusly postgreSQL is running on my server and in /etc/services i find two
rows in which it declares that port 5432 is for postgres connection...

...
***********************************************************************
Vittorio Zuccala'
ICQ#20318568
YMess: nathanvit
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