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_over          = newImage("nav_images/home-on.gif");
		contact_over       = newImage("nav_images/contact-on.gif");
		leadership_over    = newImage("nav_images/leadership-on.gif");
		mission_over       = newImage("nav_images/mission-on.gif");
		news_over          = newImage("nav_images/news-on.gif");
		directions_over    = newImage("nav_images/directions-on.gif");
		preloadFlag = true;
	}
}