What's the meaning of this warning from gkrellm?

[Miguel Daniel Rodríguez Magarzo]

El dom, 10-02-2008 a las 14:15 +0100, Miguel Daniel Rodríguez Magarzo
escribió:
> Gkrellm notifies that there are new email notifications from root
> at /var/log/<myuser>. These mails are generated because of somethings is
> wrong with the cron.daily, but I don't know how to interpret it:
> 
> ---------------------------------------------------------
> >From root at ulises Sun Feb 10 12:09:33 2008
> Return-path: <root at ulises>
> Envelope-to: root at ulises
> Delivery-date: Sun, 10 Feb 2008 12:09:33 +0100
> Received: from root by Ulises with local (Exim 4.67)
> 	(envelope-from <root at ulises>)
> 	id 1JOA3w-00073n-OM
> 	for root at ulises; Sun, 10 Feb 2008 12:09:33 +0100
> From: Anacron <root at ulises>
> To: root at ulises
> Subject: Anacron job 'cron.daily' on Ulises
> Message-Id: <E1JOA3w-00073n-OM at Ulises>
> Date: Sun, 10 Feb 2008 12:09:32 +0100
> 
> /etc/cron.daily/logrotate:
> error: firebird1.5:8 unknown user 'firebird'
> run-parts: /etc/cron.daily/logrotate exited with return code 1
> --------------------------------------------------------------------
> 
> A search with Synaptic says that something called firebird is installed
> in this system,that's a kind of SQL database, probably installed as
> dependency of other package.
> 
> 
> ............................................
> common files for firebird 1.5 servers and clients
> This package contains files common to both servers and clients for both
> super
> and classic flavours.
> 
> These include the security database, message file (firebird.msg),
> support
> scripts as well as configuration files in /etc/firebird/1.5.
> 
> Please refer to the firebird1.5-super or firebird1.5-classic packages
> for more
> information about Firebird in general.
> 
>  Homepage: http://www.firebirdsql.org/
> ............................................................................
> 
> How to avoid that messages from gkrellm? Anyone knows, please?
> Actually, it doesn't matter much IMO, but I'd like to be able to do that
> they disappear. 
> 
> Daniel
> 

No one? 

No ideas?

--8x------------------------
A forgotten web page, like my question here at the moment:
http://ploughingthemetal.galeon.com
..........................................................