function initPngs() {
    if(document.getElementById('channelPng').runtimeStyle) 
	{
	document.getElementById('channelPng').style.backgroundImage = 'none';	
    document.getElementById('channelPng').style.filter = "progid:DXImageTransform.Microsoft.AlphaImageLoader(src='/2007/TDF/img/autresepreuves_tab.png',sizingMethod='scale')";
	}
  }
addEvent(window, "load", initPngs)