function refreshCaptcha() {
    var vn = document.getElementById("validateID").value;

    document.getElementById("captchaImgID").src = "images/buscando-2.gif";

    $.ajax({
        type: "GET",
        url: "/proc_2.jsp",
        data: { actionID: 40, vn: vn },

        success: function (response) {
            var n = response.trim();

            document.getElementById("validateID").value = n;
            document.getElementById("captchaImgID").src = "images/valida/img" + n + ".png";
        }
    });
}