Comment 18 for bug 429370

I experienced this (as per my earlier comment). It drove me nuts, so I did a little digging.

Wired connections were OK if I used "wpa_supplicant" via the terminal and added "fast_reauth=0" to my configuration file. Wireless worked if I used the Wicd network manager, but Wicd doesn't support WPA over wired connections. So I've arrived at a compromise between setting up my "/etc/network/intefaces" file as follows:
"# Ethernet interface
auto eth0
iface eth0 inet dhcp
wpa-driver wired
wpa-conf /etc/wpa_supplicant/wired.conf"

That handles wired connections. Wicd handles wireless flawlessly. I hope this helps somebody, but of course your mileage may vary.