This seems like the right place for this - If anyone is having issues setting up an older Airport Express to work with one of Uverse's 2Wire Uverse modem/routers, read below, this may help.
I was struggling to get my older "G" protocol airport express to hook up as a music streamer from my new AT&T Uverse 2Wire modem. After much web searching and experimentation, it boiled down to switching the Uverse 2wire modem wireless security from the default to "WPA2 - PSK (AES)". It then was a fairly straight forward configuration with AirPort Utility 5.6.
