How to send a correct authorization header for basic authentication

I am trying to POST data from my API but I can't pass the basic authentication.

I try:

$.ajax({
  type: 'POST',
  url: http://theappurl.com/api/v1/method/,
  data: {},
  crossDomain: true,
  beforeSend: function(xhr) {
    xhr.setRequestHeader('Authorization', 'Basic [REDACTED]');
  }
});

My server configuration response is:

response["Access-Control-Allow-Origin"] = "*"
response["Access-Control-Allow-Methods"] = "POST"
response["Access-Control-Max-Age"] = "1000"
response["Access-Control-Allow-Headers"] = "*"

The headers that I get is:

Request Headers

OPTIONS /api/v1/token-auth/ HTTP/1.1
Host: theappurl.com
Connection: keep-alive
Access-Control-Request-Method: POST
Origin: http://127.0.0.1:8080
User-Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.31 (KHTML, like Gecko) Chrome/26.0.1410.63 Safari/537.31
Access-Control-Request-Headers: origin, authorization, content-type
Accept: */*
Referer: http://127.0.0.1:8080/
Accept-Encoding: gzip,deflate,sdch
Accept-Language: es,en;q=0.8
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3

Response header

HTTP/1.1 401 Unauthorized
Server: nginx/1.1.19
Date: Fri, 16 Aug 2013 01:29:21 GMT
Content-Type: text/html
Content-Length: 597
Connection: keep-alive
WWW-Authenticate: Basic realm="Restricted"

I guess the server configuration is good because I can access to API from the Advanced REST Client (Chrome Extension)

Any suggestions?

PD: The header that I get from Advanced REST client is:

    User-Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.31 (KHTML, like Gecko) Chrome/26.0.1410.63 Safari/537.31
    Origin: chrome-extension://hgmloofddffdnphfgcellkdfbfbjeloo
    Authorization: Basic [REDACTED]
    Content-Type: application/x-www-form-urlencoded 
    Accept: */*
    Accept-Encoding: gzip,deflate,sdch
    Accept-Language: es,en;q=0.8
    Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.3

and

    Server: nginx/1.1.19 
    Date: Fri, 16 Aug 2013 01:07:18 GMT 
    Content-Type: application/json; charset=utf-8 
    Transfer-Encoding: chunked 
    Connection: keep-alive
    Vary: Accept, Cookie 
    Allow: POST, OPTIONS 
    X-Robots-Tag: noindex

sending OPTION method

Solution

Note: This answer is out-of-date. While this answer may have worked for a particular case in 2013, user and passwords in the URL are now deprecated according to Mozilla and RFC 3986.

You can include the user and password as part of the URL:

http://user:[email protected]/index.html

see this URL, for more

HTTP Basic Authentication credentials passed in URL and encryption

of course, you'll need the username password, it's not 'Basic hashstring.