qmail on dmz
 

I am setting up a mail server (qmail) inside our dmz. We only have one ip address from our isp and I will be using it for our firewall.

Am using iptables on the firewall, and am allowing http and mail to the DMZ. Our internal network has the address 192.168.1.0, the dmz has 192.168.2.0. The firewall as three nic's, one to the ISP, one to the DMZ and one to the internal network.

Our apache server is already working and I am about to setup our qmail server.

I can have our ISP's DNS configure to point http and mail to the single IP address they have given us.

Reading from documentation available, Life with Qmail, etc., I did not come across configuring Qmail inside a DMZ.

Any idea how I should proceed? Do I need to run a DNS (tinydns)? Do I need to set-up another mail server inside the intnernal network? Or is it much simpler if I install qmail on the firewall?

Thanks!