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("images/home_over.gif");
	tech_over = newImage("images/tech_over.gif");
	others_over = newImage("images/others_over.gif");
	faq_over = newImage("images/faq_over.gif");
	po_over = newImage("images/po_over.gif");
	normes_over = newImage("images/normes_over.gif");
	contacts_over = newImage("images/contacts_over.gif");
	preloadFlag = true;
	}
}