Thomas, I tested out your change... I noticed a few things when I did that...
First, I can see all events in the events page. Which is good. But sadly I lose the ability to manage group permissions. Going to Advanced -> settings -> users and looking at the group permissions I see nothing there. That is important if I not only want to authentication users but also do some sort of access control for them.
Second, I started seeing zenoss failure events around handling an empty set. I have to assume its related.
Rob, I'm looking into your idea.. I think its a bit hacky...but its working so far. I'm going to continue to play with it and let y'all know how it works out.
Thanks,
Scott