El wmode, ademas de ponerlo en el param debes ponerlo dentro del embed
Código html:
Ver original<embed width="780" height="200" src="flash/vertrauen-home.swf" quality="high" pluginspage="http://www.adobe.com/shockwave/download/download.cgi?P1_Prod_Version=ShockwaveFlash" type="application/x-shockwave-flash" wmode="transparent"/>