IE9: Mouseovers on unavailable pages don't work

In Lessons, create a couple of quizzes, making the first one required
Select the following under Edit for Quiz2:
Don't Release Item Until All Prerequisites are Completed
Require that the student submit this assessment.

As the student, using IE9, log into the course
Click on Lessons
The second quiz should be 'grayed-out'
Hover over the link for the second quiz
No message displays

What should be displayed:
"Please complete all of the above required items before viewing this item."

Attaching screen shot of how this works in FF