replacing proxying dns servers ... split dns.. host files?

[Bassett, Mark]

Hi guys, I've got a question for all you gurus out there.  We are
replacing a proxying firewall that has split dns.  The firewall allows
host name type overrides for any entry you want.  Obviously this isn't
RFC compliant for a DNS server, but they would like to continue with
using that functionality if at all possible.  From my research I believe
that using split DNS with BIND (view statements) would be what I want to
implement.  However, I do not know how to get the host file type
resolution without hosting the entire zone of a site.  
 

For example:

 

Let's say for some reason we need to route mail for user at yahoo.com to a
different mail server for mail relaying.  (say we're blacklisted or some
other silly reason doesn't matter this is just for example)

 

On the current system we just pop in an mx record for yahoo.com and the
email is now re-routed to the other server.  

 

I can find no way to do this in BIND currently.  I have seen that
dnsmasq forwarding dns server can do host file overrides, but I am not
certain on how to bring that functionality into BIND.  

 

Any thoughts guys?