Preparing the Database Server for JDBC
     Out of the box, Java does not support unix sockets so the PostgreSQL server must be 
configured to allow TCP/IP connections. Starting with server version 8.0 TCP/IP
connections are allowed from
     
      localhost
     
     . To allow connections to other interfaces
than the loopback interface, you must modify the
     
      postgresql.conf
     
     file’s
     
      listen_addresses
     
     setting.
    
     Once you have made sure the server is correctly listening for TCP/IP connections
the next step is to verify that users are allowed to connect to the server. Client
authentication is setup in
     
      pg_hba.conf
     
     . Refer to the main PostgreSQL 
     
      documentation
     
     for details .