DNS and firewall

[Krzysztof Mazurczyk <kmazurczyk@wskiz.poznan.pl>]

Hi all,

I've got primary and secondary DNS (bind). And a firwewall of cause.
I would like to hide my primary DNS from externals setting it on my LAN.
Then put secondary to DMZ. 
The question is how to configure both servers that all query from externals
about my domain will be to my secondary only. I try to avoid querying
primary (which won't answer) and then secondary by externals.

My idea is to set in higher level DNS my secondary server as primary for
my domain. But I'm afraid to do something wrong.

Any ideas ?

Regards,
Chris