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) {
		intro_07_over = newImage("Bilder/intro_07-over.jpg");
		intro_09_over = newImage("Bilder/intro_09-over.jpg");
		intro_11_over = newImage("Bilder/intro_11-over.jpg");
		intro_16_over = newImage("Bilder/intro_16-over.jpg");
		intro_18_over = newImage("Bilder/intro_18-over.jpg");
		intro_20_over = newImage("Bilder/intro_20-over.jpg");
		preloadFlag = true;
	}
}