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) {
		home_off_over = newImage("images/home_off-over.gif");
		contact_off_over = newImage("images/contact_off-over.gif");
		disposal_services_off_over = newImage("images/disposal_services_off-over.gif");
		field_services_off_over = newImage("images/field_services_off-over.gif");
		transportation_off_over = newImage("images/transportation_off-over.gif");
		about_nedt_off_over = newImage("images/about_nedt_off-over.gif");
		nedt_difference_off_over = newImage("images/nedt_difference_off-over.gif");
		preloadFlag = true;
	}
}