var preloadFlag = false;

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];
		}
	}
}

function preloadImages() {
	if (document.images) {
		im1 = newImage("images/nav/about_us-on.gif");
		im2 = newImage("images/nav/cust_service-on.gif");
		im3 = newImage("images/nav/line_service-on.gif");
		im4 = newImage("images/nav/leasing-on.gif");
		im5 = newImage("images/nav/management-on.gif");
		im6 = newImage("images/nav/s_overview-on.gif");
		im7 = newImage("images/nav/s_management-on.gif");
		im8 = newImage("images/nav/s_history-on.gif");
		im9 = newImage("images/nav/s_news-on.gif");
		im10 = newImage("images/nav/s_careers-on.gif");
		im11 = newImage("images/nav/s_contact-on.gif");
		im12 = newImage("images/cond_weather-on.gif");
		im13 = newImage("images/cond_airtraffic-on.gif");
		im14 = newImage("images/cond_airport-on.gif");
		
		preloadFlag = true;
	}
}