Bind DNS for active directory child domain
 

I've setup BIND9 DNS to be the authoritative DNS for the 2003 active directory domain by creating 7 zones and allowing dynamic updates from the domain controller. Now I'm planning to add a child domain to the existing domain tree but was wondering if I need to create another 7 zones for the child domain like I did for the parent domain in Bind DNS.

So for the first domain I've created 7 zones:
DomainDNSZones.ad.test.com
ForestDNSZones.ad.test.com
_msdcs.ad.test.com
_tcp.ad.test.com
_udp.ad.test.com
_sites.ad.test.com
ad.test.com

And added the 7 entries for each zone to the named.conf file with allow-update from the DC's IP. It works great but I'm not sure if I need to do the same for the child domain or if I can just use the existing parent domain zones for the child domain since dynamic updates is allowed. I've tried googling for this (adding child domain using bind DNS) but couldn't find anything.

Anyone have experience with this?

Thanks.