client socket TIME_WAIT state after PQfinish

Dear all,

Environement:
- OS : Ubuntu 10.04 LTS.
- DB: postgresql 8.4.
- Connection to postgresql using sslmode = disable

Scenario :

1. I use pgadmin to connect/disconnect to the postgresql server on port 5432 or

2. I use a progam using libpq and make PQconnectdb and PQfinish.

Bug:

In both cases, the client socket (pgadmin or my program) remains in TIME_WAIT state.
I have used wireshark to sniff the TCP protocol.

We have at the end of a connection:

Client Server
---> FIN,ACK --->
<--- FIN,ACK <---
---> ACK --->

This ends up in a TIME_WAIT state. The TCP protocol should be

Client Server
---> FIN,ACK --->
<--- ACK <---
<--- FIN,ACK <---
---> ACK --->

I suppose there is a bug in the postgresql server that do not send an ack to the client.

Could you please clarify this situation ? I am a bit lost.

Thank you,

Franck Lefort