Sorry, i didn't read your whole question. Do you need dmz on your PS3? It's only if you are having nat type 3 issues, disconnecting from games an all that. Are you experiencing any issues that you might think are network related?
Apple Airport Extreme's router does not have a "DMZ" feature. Its equivalent is the "Enable default host at:" feature. To access this, go into Airport utility, then manual setup, then internet. From here, hit the NAT tab, and type in your PS3's static IP address at the "enable default host at" area. You'll then have to reboot the airport router, and go into the PS3's connectivity settings. You then have to manually input the static IP address you used for the enable default host at..then you should be good to go!
Just wanted to share that I attempted this and it didn't work. Well, it "works", but personally I'm still stuck in NAT Type 2.
Anyone know of a way to get NAT Type 1 with Airport Extreme? Also, have to stay wireless. There isn't a possibility of connecting directly to the Extreme with a wire.
Thanks to anyone who might have an answer.