Customize the handling of the OnClick event of embedded SWF in HTML page

I need help to handle the "onClick" event of an embedded SWF movie in a HTML page. Basically, the default behavior of an embedded SWF video is such that if you click on the embedded video, it will start playing immediately. I want to override the default behavior, e.g. by displaying a message or sending user to another web site. You can use an embedded SWF from YouTube in a page, and use Java script to customize the behavior.