<div style="width:300px; height:300px; text-align:center; padding-top:20px; background-color:Gray" onmouseout="alert('d')">
<div style="width:100px; height:100px; background-color:Blue" >
</div>
</div>。???
<div style="width:100px; height:100px; background-color:Blue" >
</div>
</div>。???
ie : e.cancelBubble