2 DHCP servers, 2 subnets, 1 physical network

Question

I am trying to add an Airport Extreme to our office network, but would like it to distribute IP addresses on a separate subnet from our primary network. Here is the basic network topology (hope it makes sense):
INTERNET
-ROUTER (DHCP Server for 192.168.1.*)
--WIRED CLIENTS (192.168.1.* clients)
--AIRPORT EXTREME (DHCP Server for 192.168.2.*, "Distribute Range of IP Addresses" mode)
---WIRELESS CLIENTS (Need to have 192.168.2.* IPs)
When I connect a wireless client, it always gets a 192.168.1.* address, but I want it to get a 192.168.2.* address. How can I force wireless clients onto that subnet and prevent the router from steal the DHCP requests?
Are there any DHCP debugging tools on OS X?
Much thanks,
/sam

Answer 1

Aha! I actually did do that before, but it gave me a Double NAT message so I tried something else. I didn't realize that it was just a warning, not an error.
Doing it this time around, I was getting errors that the public IP on my AEBS was conflicting with addresses of the private network of my AEBS. So I created yet another subnet and it seems to work great (my test is whether I can video iChat with the outside world and whether I can access my private network)
So here is my new setup:
INTERNET
-ROUTER (3 subnets: 192.168.1.0, 192.168.2.0, 192.168.3.0, DHCP serving up 192.168.1.* addresses)
--WIRED CLIENTS (192.168.1.*)
--AIRPORT EXTREME (IP: 192.168.2.1, DHCP serving up 192.168.3.*)
---WIRELESS CLIENTS (192.168.3.*)
Thank you guys so much for your help! Really made my day =)