Drop forwarded requests

[gagadget at free.fr]

Hi listers,

Is there a way to prevent BIND to answer frowarded requests ?

For local uses, somebody has setup a DNS on our network ( very large network ),
his server is forwarding all requests it can't answer. We asked him several
times to shut down his server but he won't. For security reasons, we don't do
forwarding on our servers so we would like to deny his forwarded requests
without deny all his requests.

Regards,
Gaga.