User-agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.4) Gecko/20030624
I think the problem isn't session data specifically. The log in fails
before the session begins.
Strangely this ONLY happens with macs. I have never had a problem with
PCs.
Maybe mac computers have a different default setting that could be
causing this problem?