Matthew Ceroni wrote: Subject: http://wiki.freeradius.org/Certificate_Compatibility

This error pops up quite a bit in my logs.

It will happen anytime a certificate-based EAP protocol is interrupted. Only worry about it if you are having problems specifically with some Windows Systems or are otherwise experiencing actual failures. It can happen simply due to WiFi noise and AP/controller retransmission limits.

I have tried to login to that site with my OpenID but it just keeps kicking me back to the login page. Never authenticates.

The URL is apparently old in the source; Just google "FreeRADIUS Certificate Compatibility" and you'll find the newer page. It does not require a login to view.