function twitterLogin(datastring){
    var url = "/lib/captcha/checkcaptcha.php";
    var dataString = "captchacode="+captchacode;
//    alert(dataString); 
    $.ajax({
        url: url,
        data: dataString,
        dataType: "text",
        success: function(msg){
			onCaptcha(msg); 
                 },
                error: function (xhr, ajaxOptions, thrownError){
                        return "ko"+setAjaxError("getText", xhr.status, ajaxOptions, thrownError);
                }
    });
}