8.0 Beta 4 denying network connections?

Hello,

    I've got one 7.4 installation and a brand new 8.0 beta4
    running on the same machine.

    Both installations are configured to use the same port
    (5431) to avoid reconfiguring the apps running on
    top of the DB.

    The following paragraphs illustrate the problem:

[root@mymachine root 20:52:07]# service postgres74 start
Starting PostgreSQL: ok

[vinko@mymachine sources 20:54:36]$ telnet mymachine 5431
Trying 192.168.2.69...
Connected to mymachine.mydomain.cl (192.168.0.169).
Escape character is '^]'.
null
Connection closed by foreign host.

[root@mymachine root 20:55:50]# service postgres74 stop
Stopping PostgreSQL: ok
[root@mymachine root 20:55:56]# service postgres8 start
Starting PostgreSQL: ok

[vinko@mymachine sources 20:55:07]$ telnet mymachine 5431
Trying 192.168.0.169...
telnet: Unable to connect to remote host: Connection refused

If I try connecting from localhost, I can connect without
trouble in both versions.

And, of course, the same happens with the psql client.

I tried modifying pg_hba.conf but to no avail and what I have
looks right to me.

Has the syntax for this file changed? I even tried to use the 74's
pg_hba with 80, but the results are the same.

Is there another config option I'm missing? FWIW, beta3 doesn't
behave this way.

Thanks for any insight on the issue,
--
Vinko Vrsalovic <el[|-@-|]vinko.cl>