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) {
		about_over = newImage("images/nav/nav_1/about-over.gif");
		what_can_over = newImage("images/nav/nav_1/what_can-over.gif");
		young_over = newImage("images/nav/nav_1/young-over.gif");
		learning_over = newImage("images/nav/nav_1/learning-over.gif");
		games_over = newImage("images/nav/nav_1/games-over.gif");
		faq_over = newImage("images/nav/nav_1/faq-over.gif");
		care4air_tv_over = newImage("images/nav/nav_1/care4air_tv-over.gif");
		news_over = newImage("images/nav/nav_1/news-over.gif");
		links_over = newImage("images/nav/nav_1/links-over.gif");
		preloadFlag = true;
	}
}