/**
	 * Sequence of operations needed to create the new cookie,
	 * containing informations about the theme selected.
	 * Expiration date is set as today + 1 year.
	 **/
	function cambia_tema(nome_tema,par1,par2) {
		
		var today = new Date();
		var expire = new Date();
		expire.setTime(today.getTime() + 3600000*24*365);
		deleteCookie('usertheme', par1);
		setCookie('usertheme', nome_tema, expire, par1);
		window.location=par2;
	}