function openWindow(url, width, height) {
	var dimensions = "";
	if (width) {
		dimensions += ",width=" + width;
	} else {
		dimensions += ",width=700";
	}
	if (height) {
		dimensions += ",height=" + height;
	} else {
		dimensions += ",height=500";
	}
	fenster = window.open("", "", "statusbar=no,menubar=no,toolbar=no,scrollbars=yes,resizable=no" + dimensions);
	fenster.location = url;
	fenster.focus();
}