HM_DOM = (document.getElementById) ? true : false;
   HM_NS4 = (document.layers) ? true : false;
    HM_IE = (document.all) ? true : false;
   HM_IE4 = HM_IE && !HM_DOM;
   HM_Mac = (navigator.appVersion.indexOf("Mac") != -1);
  HM_IE4M = HM_IE4 && HM_Mac;

 HM_Opera = (navigator.userAgent.indexOf("Opera")!=-1);
 HM_Konqueror = (navigator.userAgent.indexOf("Konqueror")!=-1);

HM_IsMenu = !HM_Opera && !HM_IE4M && (HM_DOM || HM_NS4 || HM_IE4 || HM_Konqueror);

HM_BrowserString = HM_NS4 ? "NS4" : HM_DOM ? "DOM" : "IE4";


	document.write ('<div style="position: absolute; top: -20; right: 29px; z-Index: 1000; height: 20px; " id="backtotopDIV"><a href="#" style="font-family: Verdana, Arial, Helvetica, sans-serif; font-size: 11px; color: black;"><img src="/images/naarboven.gif" border=0></a></font></div>');

	function set_backtotop () {
		if (HM_IE) {
			document.all.backtotopDIV.style.pixelTop = document.body.clientHeight - document.all.backtotopDIV.style.pixelHeight + document.body.scrollTop;
			if (document.body.clientHeight >= document.body.scrollHeight || document.body.scrollTop == 0) {
				document.all.backtotopDIV.style.visibility = 'hidden';
			} else {
				document.all.backtotopDIV.style.visibility = 'visible';
			}
		} else {
			document.layers.backtotopDIV.clip.top = window.innerHeight - document.layers.backtotopDIV.clip.height;
		}
	}

	function activate_backtotop () {
		t = window.setTimeout("set_backtotop()", 500); 
	}

	if (HM_IE) { 
		set_backtotop();
		onscroll = activate_backtotop;
		onresize = activate_backtotop;
	} else {
		ti = window.setInterval("set_backtotop()", 50); 
	}