function add_mail(element_value) {
    if ((element_value != "enter email address") && (element_value != "")) {
        $.ajax({
            type: "GET",
            url: "/post_mail.aspx",
            data: "element_value=" + element_value,
            cache: "false",
            success: function(r_value) {
                switch (r_value) {
                    case '0':
                        alert("Your email address is already on the mailing list.");
                        break
                    case '1':
                        $("#mail_submit").attr("onclick", "");
                        $("#mail_sign").val("");
                        $("#submit_text").html("Thank You");
                        break
                    default:
                        alert("Invalid email address.");
                        break
                }
            }
        });
    } else {
        alert("You need to enter an email address");
    }
}
function textCounter(field, maxlimit) {
    if (field.value.length > maxlimit)
        field.value = field.value.substring(0, maxlimit);
}