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) {
		nHom_over = newImage("images/nHom2.gif");
		nAbt_over = newImage("images/nAbt2.gif");
		nMed_over = newImage("images/nMed2.gif");
		nFac_over = newImage("images/nFac2.gif");
		nSer_over = newImage("images/nSer2.gif");
		nApp_over = newImage("images/nApp2.gif");
		nCon_over = newImage("images/nCon2.gif");
		nMap_over = newImage("images/nMap2.gif");
	}
}