DNS pointing to domain without www.?

[Jake Odell]

Hm..  don't arpa PTR RR's essentially exist for domain A records, with (possibly multiple) CNAME's "resolving" to a host with an A record?   Don't reverse lookups only occur for IP addresses?

What would be wrong (or unusual) with in the domain zone:

domain. IN NS ns.domain., admin.domain. 
...
machine IN A 192.168.0.10  ;points to an IP address
smtp IN CNAME machine  ;points to a host name
pop IN CNAME machine  ;ditto
ns IN CNAME machine  ;ditto
domain. IN MX 10 machine
...

and in arpa zone:

...
10.0.168.192.in-addr.arpa. IN PTR machine.domain.
...

??

where would resolution, reverse or otherwise, break down for ns, pop, or smtp?
How else would you do it?
  Shaun Joseph <Shaun.Joseph at usa.alcatel.com> wrote in message news:37963EAC.77A1769D at usa.alcatel.com...
  Media Master wrote: 
  --8<--

  In general (and certainly in this case) you DON'T want to have two canonical names for the same IP address.  It (probably) won't break anything if you do, but it's bad form and breaks consistency with your inverse pointers. 

  --8<--