Unable to create DNS forwarder in my AD integrated DNS

Hi,

I have my mix AD servers (2003 + 2008) and im trying to create DNS forwarder to send requests to outside the Domain over natted IP for the name resolution. However, it works perfectly fine in my test environment.

Now, when i try to create on my production server, i get below error:

The operation requested is not permitted on the root DNS server

Please suggest.