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) {
		btn_events_over = newImage("images/btn_events_over.gif");
		btn_training_over = newImage("images/btn_training_over.gif");
		btn_tickets_over = newImage("images/btn_tickets_over.gif");
		btn_interactive_over = newImage("images/btn_interactive_over.gif");
		btn_arena_over = newImage("images/btn_arena_over.gif");
		btn_map_over = newImage("images/btn_map_over.gif");
		btn_home_over = newImage("images/btn_home_over.gif");
		preloadFlag = true;
	}
}