If you’ve used  Flash and DHTML on the same page may have come across this problem. In most browsers Flash will always display above other layers. So if you have have a CSS drop-down menu or pop-up lightbox image gallery, you will find the Flash element obscures your DHTML layer.

The Solution

You will need to add the param ‘wmode’ to the  <object> tag with a value of  ‘opaque’ – like this:

param name="wmode" value="opaque"

If you are using <embed> the ‘wmode’ attribute should be added:

wmode="opaque"

Flash & Dreamweaver generate a javascript file when adding Flash to an HTML page so the attribute needs to be added to this as well. In Flash, this can be set in the ‘publish’ options dialogue box before exporting the HTML file. In dreamweaver it needs to be added to the javascript on the page:

AC_FL_RunContent( 'codebase','http://download.macromedia.com/pub/shockwave
/cabs/flash/swflash.cab#version=9,0,28,0','wmode','opaque',....