[Mimedefang] Soliciting opinions on filtering based on bad MX records

[David T Hollis]

Michael Sims wrote:

>  # This hash defines a list of IPs and networks that are bogus when
>  # used as an MX.  This list should contain any non-routable network,
>  # such as loopback or reserved addresses. Each entry should be a
>  # subnet/netmask pair.  To specify a single host, use 255.255.255.255
>  # as the netmask
>  my %bogusMXs = (
>
>    '0.0.0.0'     => '255.255.255.255',
>    '127.0.0.0'   => '255.0.0.0',
>    '10.0.0.0'    => '255.0.0.0',
>    '172.16.0.0'  => '255.240.0.0',
>    '192.168.0.0' => '255.255.0.0'
>
>  );
>
> 
>
I wonder if it would be useful to check against 'bogon' networks as well 
(http://www.iana.org/assignments/ipv4-address-space).  May be a little 
bit tedious maintaining, though it doesn't change that often.