How do you change the background param of the SharePoint 2010 Silverlight webpart

I'm using the SharePoint 2010 Silverligh开发者_Go百科t webpart to display a Silverlight application within a SharePoint site. The object tag emitted by the webpart includes this parameter:

<param name="background" value="white" />

I'd like to change this to black instead of white but I don't see anyway to control this. Setting the .BackColor property to black had no effect. Is there a way to do this or am I forced to always use a white background with this webpart?

Confirmed with Microsoft today that it is not possible to control this parameter with the out-of-the-box Silverlight web part. To change this parameter you must change it with client side JavaScript or build your own web part to emit the desired HTML.