agregale al flash esto:
<param name="wmode" value="transparent">
y la forma correcta de poner un flash seria esta:
Código:
<object type="application/x-shockwave-flash" data="Flash/Slideshow2/slideshow2.swf" width="149" height="96">
<param name="allowScriptAccess" value="sameDomain" />
<param name="movie" value="Flash/Slideshow2/slideshow2.swf" />
<param name="quality" value="high" />
</object>