Airport Extreme (802.11n) and ATT U-verse wireless router (2-wire)

I am attempting to use my new airport extreme with my new U-verse service. Prior to the U-verse service my router worked fine. I have to use the U-verse router as it is the brains behind the internet/TV applications of the U-verse service. I tried to run a eithernet cable from the U-verse router to the Airport Extreme, but the U-verse router says that I cannot use a third-party router behind the U-verse router. The U-verse router gives me the option to resolve the problem and it makes some configuration changes. The U-verse router show my Airport Extreme as a DMZ+ device. I can use my computers that are on the Airport Extreme network but my Xbox's will not work.

Is there a way to use the Airport Extreme as a wireless hub and not have the Airport Extreme compete with the U-verse router to assign IP addresses?

Thanks,

Larry

Just switched to Macs and never want to go back to Windows!