I tried it on the sampler that comes with the package to replicate the bug, on the simple menu bar there.
I first noticed it in my application. The problem is that when the menu expands, the IE7 tab starts a cicle as if refreshing, as seen in the picture below, and only afterwards it manages to draw the select as you go over the drop down list in the menu, and only afterwards it does the action too.
EDIT: The issue here is that it takes a few seconds to do it.
