[flexcoders] Drag image underneath another component

[Kevin]

I have an image that is underneath a "box" component and I will like  
to be able to drag the image, but can't seem to do so unless I place  
it on top of the Box.  Any ideas?  - Kevin

<mx:Canvas width="450" height="350" horizontalScrollPolicy="off"  
verticalScrollPolicy="off" >
		<mx:Image id="myImage" source="assets/temp/mytestimage.jpg"  
mouseDown="handleStartDrag(event);" mouseUp="handleStopDrag(event);"/>
		<mx:Box id="myBox" width="450" height="350"  
backgroundColor="0x999999" backgroundAlpha=".5" />
</mx:Canvas>