When I embedded SWF I used the following:
<object classid="clsid:D27CDB6E-AE6D-11cf-96B8-444553540000" codebase="http://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=6,0,0,0" height="450" width="700">
<param name="movie" value="UYBC-intro.swf">
<param name="quality" value="best">
<param name="play" value="true">
<embed height="450" pluginspage="http://www.macromedia.com/go/getflashplayer" src="UYBC-intro.swf" type="application/x-shockwave-flash" width="700" quality="best" play="true">
</object>
But that doen't validate either.