dblink_connect is slow

Hi

Using Postgresql 8.2 on Linux, I am trying to use dblink contrib to connect to a remote Postresql 8.2 database. I am using the following SQL :

select dblink_connect('host=remote_server port=5432 dbname=remote_bdd user=remote_user password=remote_pwd');

The problem is :
- when remote_server entry exists in /etc/hosts file, the connexionis immediate
- but when remote_server entry does not exists in /etc/hosts file, the connexion take 1 minute

However, even if remote_server entry does not exists in /etc/hosts file, I can ping immediately the remote_server and a remote psql connexion (using "psql -h remote_server -d remote_bdd") is also immediate, so I don't think that my network or DNS server could be the problem

Is the something particular with dblink_connect function that could explain that a remote connexion is so long ?

Thank you by advance fore your help

Jeff