function refreshCaptcha(){
     jQuery.post(captchaNewKeyUrl, { new_key: "1"}, function(data) {
        get='?';
        for( i in captcha ) {
            get = get+i+'='+captcha[i]+'&';
        }
        var strLen = get.length;
        get = get.slice(0,strLen-1); 
        url = "http://www.vizitatori.com/captcha/file-"+data+".php"+get;
        jQuery("#imgCaptcha").attr("src", url);
        jQuery("#captchaHash").attr("value", data);
    });
};