Well that's the weirdest thing. I've seen this kind of thing before, so I guessed that <--> would work. But the page asks my browser to store information. If I ignore the question and just allow the query to continue to display at the top of the window, I can navigate fine. If I say "Not now," I'm stuck on whatever page I was on when I answered, and have to reload to be able to move again.
Ubuntu 11.10, FF recent.