So for a while now, I've had to use SharkScope in Camino. It turns out, though, that if you use the "Develop" menu in Safari to change the user agent to Opera for mac, the page will work correctly. I managed to get the page sort-of working with the IE5 user agent as well, but the login widget wouldn't work. Opera for mac, however, seems to do the trick.
It's also possible, however, that the whole thing is just a heisenbug, and that it just happened to work best when I picked Opera. I rather doubt that the SharkScope developers test their site with Safari (though now that they can get Safari for Windows, they have less of an excuse).