[dns-operations] Reporting glue as authoritive data -- Bug!

[Paul Vixie]

> > Sendmail used QTYPE=3DANY to retrieve A and AAAA records in one query.
> > I guess quite a few mail servers still do this, so it should better
> > work, at least to some degree.
> 
> 	Sendmail used ANY to work around a BIND [48] bug with
> 	misconfigured zones.

no, really, it didn't.  sendmail used ANY because if there was an MX in the
cache it would come, and if there was an A in the cache it would come, and
if both were in the cache both would come.  this was an opportunistic attempt
to save on round trips.  i have this directly from the original author of the
MX logic in sendmail.