function newImage(arg) {
	if (document.images) {
		rslt = new Image();
		rslt.src = arg;
		return rslt;
	}
}

function changeImages() {
	if (document.images && (preloadFlag == true)) {
		for (var i=0; i<changeImages.arguments.length; i+=2) {
			document[changeImages.arguments[i]].src = changeImages.arguments[i+1];
		}
	}
}

var preloadFlag = false;
function preloadImages() {
	if (document.images) {
		pre_home_over = newImage('daten/head/home_over.gif');
		pre_kontakt_over = newImage('daten/head/kontakt_over.gif');
		pre_impressum_over = newImage('daten/head/impressum_over.gif');
		pre_home_out = newImage('daten/head/home_out.gif');
		pre_kontakt_out = newImage('daten/head/kontakt_out.gif');
		pre_impressum_out = newImage('daten/head/impressum_out.gif');
		
		preloadFlag = true;
	}
}

function popupWindow(url) {
  window.open(url,'popupWindow','toolbar=no,location=no,directories=no,status=no,menubar=no,scrollbars=yes,resizable=no,copyhistory=no,width=500,height=580,screenX=150,screenY=150,top=150,left=150')
}