Unix BIND DNS & Window 2000 DDNS Integration

[Viet.Tran at isd.CO.Santa-Clara.CA.US]

Hi,

We currently have Unix DNS with BIND 8.2.3 to support about 50 subdomains.
Each group of subdomains has its own email server.  The Unix DNS is also
the central mail relay for all subdomains.  We plan to migrate to Windows
2000 Active Directory for the majority of these subdomains.  If we delegate
a subdomain for Windows 2000 DDNS Active Directory, we will also have to
change current mail addressing scheme, won't we?  Besides such a delegation
do we have any other option without affecting mail functionality?  Can we
have two primary servers -- one Windows 2000 DDNS, one Unix BIND 8.2.3 --
serving at the same time authoritative role right from the local top level
domain?

Thank you.

Viet.