Why Placeholder DIV cannot trigger MouseOver layer?

[Markku]

I've created a placeholder for DIV and try to set that element as a link so that it would show content above it on the MouseOver layer but it doesn't work. It won't even show a popup layer.

It works immediately when I turn the object into a regular object.

I can't see a reason for this but would like to know if this a known limitation?

Source file for MouseOver scanerio is attached.