[ubuntu-uk] aptitude/dpkg and a post-install script failing

[Gavin Ford]

Hello,

I'm getting a strange error message from aptitude when I install anything or 
run safe-upgrade.  It's caused by what it tells me is a the failing post-
installation script for ssmtp.

Now I have ssmtp installed and working fine on two machines, but both throw 
this error out:

> The following partially installed packages will be configured:
>   ssmtp 
> 0 packages upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
> Need to get 0B of archives. After unpacking 0B will be used.
> Setting up ssmtp (2.61-12ubuntu1) ...
> hostname: Unknown host
> dpkg: error processing ssmtp (--configure):
>  subprocess post-installation script returned error exit status 1
> Errors were encountered while processing:
>  ssmtp
> E: Sub-process /usr/bin/dpkg returned an error code (1)
> A package failed to install.  Trying to recover:
> Setting up ssmtp (2.61-12ubuntu1) ...
> hostname: Unknown host
> dpkg: error processing ssmtp (--configure):
>  subprocess post-installation script returned error exit status 1
> Errors were encountered while processing:
>  ssmtp

So it looks like the configure script couldn't indentify my hostname, no real 
problem as I configured it by hand.  But is there a way to tell dpkg to stop 
trying to configure it?

I could just mess with the script in question, which I think is
/var/lib/dpkg/info/ssmtp.postinst but I wanted to know if there is a "proper" 
Ubuntu/Debian way to do it.

  -Gav