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) {
		btn_home_over = newImage("images/btn_home-over.jpg");
		btn_about_over = newImage("images/btn_about-over.jpg");
		btn_services_over = newImage("images/btn_services-over.jpg");
		btn_auction_over = newImage("images/btn_auction-over.jpg");
		btn_picture_over = newImage("images/btn_picture-over.jpg");
		btn_trucks_over = newImage("images/btn_trucks-over.jpg");
		btn_contact_over = newImage("images/btn_contact-over.jpg");
		btn_parkingLot_over = newImage("images/btn_parkingLot-over.jpg");
		preloadFlag = true;
	}
}