Problem with Windows XP Pro SP3 asn PostgreSQL 8.3.5

Hello everybody. In the last week i'm having a trouble with my
PostgreSQL working on Windows XP Professional.

When i boot, Postgresql works correctcly, but after about an hour it
stops working, an i get timeouts when i try to connect to it.

In the postgresql log, i get this message: 2009-03-25 10:52:57 CET
FATAL: could not duplicate socket 1276 for use in backend: error code 10022

After this, if i go to Event Viewer, i get this warning: PostgreSQL
Database Server 8.3 Service stopped.

In task manager, i get two postgres.exe process running, the first
one of 104 Kb, and the second about 5000 kb.

If i try to start postgresql service again, I got these messages:
Waiting for server startup...
LOG loaded library "$libdir/plugins/plugin_debugger.dll"
LOG could not bind IPv4 socket: No error
HINT is another postmaster already running on port 5432? If
not, wait a few seconds and retry.
WARNING: could not create listen socket for "*"
FATAL: could not create any TCP/IP sockets

The service appears as starting, but it does not start.
If i kill the two postgresql porcessess the one of 5000kb stops
correctly, but i get access denied for killing the one of 104 Kb.

If i try to start postgresql service again, i can't, because it
stills starting, and i can't do anithing to it.

The only way is reboot the machine, but after about an hour, the
same history.

Before i detected this trouble last week, i had never got any problem

any idea?

King Regards