[twitter-dev] Failed to validate oauth signature and token with xauth

[ntortarolo]

Hi, i have problem requesting an access_token, i think my source is
right, i dont know where is the problem, i have maken some test with
base_string,  oauth_consumer_key and oauth_consumer_secret shown on
http://dev.twitter.com/pages/xauth and i get the same oauth_signature
shown there so i think problem is not there when i use the real
base_string, my oauth_consumer_key and oauth_consumer_secret.
        My source is this, i hope someone can help me (to preserve my secret
and key i will put the same as the ones used on 
http://dev.twitter.com/pages/xauth)

        xauth: function xauth()
        {

         var username = encodeURIComponent("aaaa"),
             password = encodeURIComponent("bbbb"),
             url= "https://api.twitter.com/oauth/access_token";,
             key = "sGNxxnqgZRHUt6NunK3uw",
             timestamp = (new Date()).getTime(),
             nonce = Math.random();

        var access_token = "oauth_consumer_key=" + key +
        "&oauth_nonce=" + nonce +
        "&oauth_signature_method=HMAC-SHA1" +
        "&oauth_timestamp=" + timestamp +
        "&oauth_version=1.0" +
        "&x_auth_mode=client_auth" +
        "&x_auth_password=" + password +
        "&x_auth_username=" + username;

        var base_string = "POST&" + encodeURIComponent(url) + "&" +
encodeURIComponent(access_token);

        var oauth_signature =
b64_hmac_sha1("5kEQypKe7lFHnufLtsocB1vAzO07xLFgp2Pc4sp2vk&",
base_string);

        oauth_signature = encodeURIComponent(oauth_signature+"=");

        var auth_header = 'OAuth oauth_nonce="' + nonce + '"' +
        ', oauth_signature_method="HMAC-SHA1"' +
        ', oauth_timestamp="' + timestamp + '"' +
        ', oauth_consumer_key="' + key + '"' +
        ', oauth_signature="' + oauth_signature + '"' +
        ', oauth_version="1.0"';

        $.ajax({
             url:url,
             method: "POST",
             data: {
                     x_auth_username: username,
                     x_auth_password: password,
                     x_auth_mode: "client_auth"
             },
             beforeSend: function(xhr){
                     xhr.setRequestHeader("Authorization", auth_header);
             },
             success: function(data){
                     alert(data);
             },
             error: function(xhr){
                     alert(xhr.responseText);
             }
        }) ;



        * What language or library are you using? What versions?
          i'm using it on javascript

        * What oauth application is this for?
        http://twitter.com/apps/edit/181924