Hmmm. Some interesting behaviours trying to access from the office. It could be related to being behind a firewall which accesses a proxy server. When I access the site using ie6, front page shows up ok, then the url not found error - seems to be pointing to the login-expired page. So for whatever reason, the login is expiring - I verified this using Firebird (very nice) which put up a the proper login expired page. Could this be related to caching on the proxy?
Next, I tried hitting the login/register link and that let me login and view my profile and whatnot but, when I click the main site link it puts me back to the index page but not logged in - yet I can access all the admin links and it shows me logged in.
Interestingly when I tried to login on openacs.org, It seemed to let me log in ok but when I tried to post, it booted me back to login. I changed a setting in ie to check for new versions of pages automatically instead of every visit and was able to post here ok. The new setting didn't help with logging in on physworx.com - same problem.
In another thread, it was suggested I telnet to my site to see what the http headers are but I don't have telnet installed on the box as it was my understanding that it's a nasty security hole. Any other thoughts?