Webmin is managing fine the database.
The problem was that yes, the host IP was supplied (unnecesarily) in the Postgres configuration.
Thank you very much and have a happy new year.

From: Jamie Cameron <jcameron@webmin.com>
To: Francisco Leovey <fleovey@yahoo.com>; Webmin users list <webadmin-list@lists.sourceforge.net>
Sent: Tuesday, December 27, 2011 3:45 PM
Subject: Re: [webmin-l] No START button on PostgreSQL page

On 27/Dec/2011 04:51 Francisco Leovey <fleovey@yahoo.com> wrote ..
> Hello and merry Xmas!
> I just installed Webmin Version 1.570 on Linux (Ubuntu Linux 11.04) - a new server
> installation
> I also installed PostgreSQL version 9.0.6 , configured the module and everything
> runs OK (We have 5 more servers with webmin and Postgres)
> For some reason (and only on this server) the postgresql module in webmin does
> not show the START btton above the Backup databases button
> I can start and stop postgres from the System-> bootup and shutdown page
> The start and stop commands are the same as the ones configured in the postgresql
> Module Config and I can also do it from the command prompt
> I also chequed and there is not another pid running for postgres
> Rebooting the Ubuntu did not help
> Any pointers?    Thank you

So does Webmin show your PostgreSQL databases and let you manage them?

The only case where the start and stop buttons wouldn't appears if it Webmin thinks
PostgreSQL is running on a remote system. This can be configured on the Module Config
page, via the "PostgreSQL host to connect to" field.

- Jamie