Understanding IN-ADDR.ARPA in a multi-zone, multi subnetted

At a country wide enterprise, with a class B subnet of 10.x.x.x, one

per city office that roughly corresponds to a child zone (eg.

can I/ do I create a x.10.IN-ADDR.ARPA for each site
or do I create a 10.IN-ADDR.ARPA zone for everything, but then how

do I get that info to each site as making each DNS server
would lead to too many replicas.

Yes Brad, this is the client I've discussed here before, and I think that this may be an alternate fix in addition to this being needed for

DDNS for our DHCP sites to work without generating errors.

Andy Konecny
Ainsworth Inc. in Toronto
[sometimes being certifiable is more fun than being certified :]