I have a setup with four Linksys E4200 wireless routers all sharing the same SSID. All are configured to authenticate against the same freeradius server via WPA 2 enterprise. I have freeradius (2.1.7) setup to authenticate against activedirectory using ntlm_auth via TTLS and mschap. Android and iOS connect correctly with this setup. Windows connects correctly as well, but is using PEAP instead of TTLS. The problem occurs with OSX (running latest build - 10.6.8). When connecting via Airport, it connects, then the text "Authenticated via TTLS" briefly appears, then it switches back to saying "Authenticating..." During this time the wireless will remain connected for 2-3 hours, until it disconnects. After that, Airport prompts for the wireless username / password again (even though these are supposed to be automatically remembered). Turning off / on airport always resolves the issue and gives another 2-3 hours of connectivity. The error occurs in four macbook pro's tested. Thanks so much for any help! If someone could point me in some direction, that would be great. The log containing the conversation between an OSX machine and freeradius is available at: http://nofouls.com/images/radlog.txt