Brent Allsop Added this (Feb 27, 2008):
The canonizer algorithm problem had to do with an attempt to set the not modified since header on a page. Aperently, if apachie saw this value on the topic page, even if you changed the canonizer (changing the page) apachie thought the page didn't need to be regenerated. So you got an old canonizer algorithm. This has been turned completely off, so the problem no longer exists.
As far as the login state. I am unable to reproduce any of this. Perhaps this behavior could happen if you have multiple canonizer windows open. Multiple sessions could of course have different canonizer algorithms set, affecting other windows in various apparently random ways. This shouldn't be to much of a problem, because if it is not in the state you want, for whatever reason, you should be able to login or out as you desire.