onerror = errortrap;
	window.onerror =errortrap;

	function errortrap() {
		return true;
	}
	
	var path = "http://www.molgen.mpg.de/pics/2001/";
	var buttons = new Array();
	var isNN = false;
	var isIE = false;
	var navName = navigator.appName;
	var navVersion = (navigator.appVersion).substring(0,3);
	if ((navName == "Netscape") && (navVersion >= 4.5)) { isNN = true; }
	if ((navName == "Microsoft Internet Explorer") && (navVersion >= 4)) { isIE = true; }	
		
	function frameCheck() {
		if (self.parent.frames.length != 0) { self.parent.location=document.location; }
	}
	
	function swapImage (name, statusText) {
		this.name = name + "_but";
		this.off = new Image();
		this.off.src = path + "mhead2001_" + name + "_off.gif";
		this.on = new Image();
		this.on.src = path + "mhead2001_" + name + "_on.gif";
		this.statusText = statusText;
	}
	function imgOn(num) {
		if (document.images) { 
			self.status = buttons[num].statusText;
			document.images[buttons[num].name].src = buttons[num].on.src; 
		}
	}
	function imgOff(num) {
		if (document.images) { document.images[buttons[num].name].src = buttons[num].off.src; }
	}
	if (document.images) {
	buttons[0] = new  swapImage ("home","Home");
	buttons[1] = new  swapImage ("contact","Contact");	
	buttons[2] = new  swapImage ("search","Search and Sitemap");
	}
	self.defaultStatus = document.title;
	onload=frameCheck;