Why would I have got exim4 installed on one system but not on another?

[Chris G]

On Sun, Jan 25, 2009 at 02:55:14PM +0100, Mario Vukelic wrote:
> On Sun, 2009-01-25 at 13:27 +0000, Chris G wrote:
> > I have three xubuntu 8.10 systems installed here, one has exim4 on it,
> > the other two don't - they appear to have no mail delivery system on
> > them at all.
> 
> Ubuntu packages should in general not depend on a particular MTA, but on
> the virtual package mail-transport-agent, which is provided by the
> following packages: citadel-mta, courier-mta, esmtp-run,
> exim4-daemon-heavy, exim4-daemon-light, masqmail, msmtp-mta, nbsmtp,
> nullmailer, postfix, sendmail-bin, ssmtp, xmail.
> Only if a general MTA is not sufficient, but the package really requires
> as specific one should it depend on this MTA directly.
> 
> However, some packages (probably from the universe repo) still
> incorrectly install exim4 if you have no package installed that provides
> mail-transport-agent installed (which is the Ubuntu default).
> 
Ah, that would explain why I got exim4 installed then, thanks.

> You can find out what packages depend on exim 4 by "apt-cache rdepends
> exim4". It's quite a list.
> 
.... and now I know why I got exim4 installed, it's because I
installed mutt.

That's cleared everything up, thanks!  I think I'll stay with exim4
although I actually know postfix better.

-- 
Chris Green