var preloadFlag = false;
function preloadImages() {
	if (document.images) {
		btn_mission_over = newImage("images/menu/btn_mission_over.gif");
		btn_valeurs_over = newImage("images/menu/btn_valeurs_over.gif");
			btn_2sante_over = newImage("images/menu/btn_2sante_over.gif");
			btn_2travail_over = newImage("images/menu/btn_2travail_over.gif");
			btn_2part_over = newImage("images/menu/btn_2part_over.gif");
		btn_clients_over = newImage("images/menu/btn_clients_over.gif");
		btn_services_over = newImage("images/menu/btn_services_over.gif");
			btn_2prev_over = newImage("images/menu/btn_2prev_over.gif");
			btn_2gest_over = newImage("images/menu/btn_2gest_over.gif");
				btn_3eval_over = newImage("images/menu/btn_3eval_over.gif");
				btn_3reins_over = newImage("images/menu/btn_3reins_over.gif");
			btn_2interv_over = newImage("images/menu/btn_2interv_over.gif");
		btn_reseau_over = newImage("images/menu/btn_reseau_over.gif");
		btn_docu_over = newImage("images/menu/btn_docu_over.gif");
		preloadFlag = true;
	}
}