an A record for a domain on a different subnet than the DNS server and
related domains in question was created and works okay for forward lookups.  
but it fails to create the PTR record for reverse lookups apparently because
the IP address is on a different subnet than the DNS server and its other PTR
records that it has authority for ( e.g. 0.0.168.192.in.addr.arpa is zone for
existing PTR records and new PTR record is on 172.16.0.0 subnet ).  does an
entire new zone have to be created for this ?  and can this zone be created
on the existing DNS server that is not actually on that subnet ?  and, if so,
what are the specific steps to do that ( as the DNS Server apparently wants
to add records for its own subnet ) ?  tia for any help on this one.