Mouse cursor never turns to pointing finger for links
I just upgraded my 2009 MacPro from Snow Leopard to Mountain Lion. Everything works great EXCEPT my mouse. When I use any browser the mouse pointer never turns to a pointing hand when it hovers over a link. I've tried in three different browsers, and two different mice. All links work as they should when I click on them, but its flippin' hard to tell what's a link and what isn't if the cursor never changes. I've read this forum and I gather lots of people had trouble with mouse cursor's disappearing or flickering after upgrade; I don't have that issue, but there's just no response at all when I hover over a text or graphic link in any browser. I can force the cursor to turn into a pointer temporarily by clicking CMD + TAB, but then it instantly reverts to an arrow or text I-bar thingy.
Tech details
Mountain Lion 10.8.4
2.66 Ghz Quad Core Xeon
12 GB RAM
wired mice (Cyborg RAT 7 and Razer DeathAdder)
Tested in Chrome, Firefox, and Safari. All exhibit the same behaviour.
I'm at wits end, and its really affecting my ability to work. Anyone have any notions of a solution?
Mac Pro, OS X Mountain Lion (10.8.4)