Comment 59 for bug 1171342

I see the same issue after upgrading (yes, just recently, I'm a slacker) to 13.10 from 13.04, on evince and nautilus. I too am running XFCE. (Specifically 4.10)

Hovering over those applications and using the scroll wheel still raises them, just as if I'd clicked on them, but does not scroll them.

"click scrolling" (as described above by Willy) does cause the applications in question to scroll. The click functionality of my scrollwheel is normal unix middle button behaviour.

I will try the PPA listed above and report back.