LAN connection to server only after restart server

Hi,

I have strange behaviour on my LAN.

Postgresql server is up and running, accepting connection on default port.
Firewall is set well.
Connection from 'localhost' is OK.
Connection from another host on LAN is refused (sniffed with wireshark:
request ACK, response RST, ACK) and so application shows 'Can't connect
to DB server' and dies.

After restart Postgresql server, nota bene _WITHOUT_ changing any bit of
configuration files, all stuff work (connections from localhost and
connections from LAN too)

In /etc/rc5.d/ postgresql server is started after network and after firewall.

It isn't so serious problem for me, only boring one, because each morning
I must start server box and then manually restart posgresql server.

All boxes runs Mandriva 2008.0

Any clue?
Thanks in advance

Pietro