透明flash的背景怎么该

-- 网页透明flash代码
<OBJECT classid="clsid:D27CDB6E-AE6D-11cf-96B8-444553540000"
codebase="http://download.macromedia.com/pub/shockwave/cabs/flash
/swflash.cab#version=5,0,0,0"
WIDTH=550 HEIGHT=400>
<PARAM NAME=movie value="Movie2.swf">
<PARAM NAME=quality value=high>
<PARAM NAME=wmode value=transparent>
<PARAM NAME=bgcolor value=#FFFFFF> <!--用flash导出后将背景改为黑色，其目的是便于观察透明效果-->
<EMBED src="Movie2.swf" quality=high wmode=transparent bgcolor=#FFFFFF WIDTH=550 HEIGHT=400 TYPE="application/x-shockwave-flash" PLUGINSPAGE="http://www.macromedia.com/shockwave/download/index.cgi?P1_Prod_Version
=ShockwaveFlash"></E