I'm most interested in this topic because I'm working on the exact same task with AT&T Uverse router configurations. I posted my progress in http://www.backtrack-linux.org/forum...ad.php?t=50963 this thread.
I'm pretty sure the default WPA PSK is derived from the BSSID somehow, because the serial number is just the decimal form of the BSSID. Using some kind of hashing function makes sense, because it's easy to ensure uniform output. I don't think there is any setup executable available for these routers, but I'm excited to try some different hashing methods to see what I get.