Hit buttons

I have a scene where I have hit buttons (hit areas) for various objects and there are places where 2 hit areas overlap. In this situation, the hit area on top will react to a mouse rollover event but the one underneath it is obscured and will not react to onrollover.
Without using swapDepths or setDepth functions (since the hit areas need to be active at all times), is there a way to overcome this problem?

Thanks in advance.