Hi globulus,
It is all in the code, that holds the flash object:
<object classid="clsid:D27CDB6E-AE6D-11cf-96B8-444553540000" codebase="
http://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=6,0,29,0" width="100%" height="100%">
<param name="movie" value="globulusFlash.swf">
<param name="wmode" value="transparent">
<param name=quality value=high>
<embed src="globulusFlash.swf" quality=high wmode="transparent" pluginspage="
http://www.macromedia.com/shockwave/download/index.cgi?P1_Prod_Version=ShockwaveFlash" type="application/x-shockwave-flash" width="100%" height="100%"></embed>
</object>
Notice the two sentences:
<param name="wmode" value="transparent"> and wmode="transparent" which tells the browser/flash player to make the flash transparent against a html background.
I hope this solves your problem.