Update profile image

[Sean]

I have been trying for a while to get the update_profile_image method
to work without much luck.  I have been able to successfully call
several other methods including ./friendships/create/ and account/
verify_credentials.xml, but have been having trouble with this method.

The exception returned is: The remote server returned an error: (403)
Forbidden.
And the status on the exception is: ProtocolError

I have verified that the image I am trying to upload will upload using
the settings page on my Twitter account.  It is a 30x30 jpg.

I am using c# and the HttpWebRequest class.  I am sure there is a
problem with how I am generating the multi-part form data because if I
change the name of the "image" parameter I get the same message which
I think means the service can't parse the request data the way I am
sending it.

Code is below along with the error message and response object I get
back from the server.  If anyone has any ideas about what I am doing
wrong I would really appreciate the help.  Thanks.

Code:
        private void UploadFile(string filename)
        {
            string url = @"http://twitter.com/account/
update_profile_image.xml";

            HttpWebRequest request = (HttpWebRequest)WebRequest.Create
(url);

            string boundary = "------------7d72b92a170f1a";
            string headerBoundary = "----------7d72b92a170f1a";  //
two dashes less than boundary
            string newline = "\r\n";

            request.ContentType = "multipart/form-data; boundary=" +
headerBoundary;
            request.Method = "POST";

            MemoryStream data = new MemoryStream();
            StreamWriter sw = new StreamWriter(data);
            sw.Write(boundary + newline);

            // Write file to data
            sw.Write("Content-Disposition: form-data; name=\"image\";
image=\"{0}\"{1}", filename, newline);
            sw.Flush();

            byte[] file = File.ReadAllBytes(filename);
            data.Write(file, 0, file.Length);

            sw.Write(newline);
            sw.Write(newline);

            sw.Write("{0}--{1}", boundary, newline);
            sw.Flush();

            // write data to request
            request.ContentLength = data.Length;
            request.Headers.Add("Authorization", "Basic " +
System.Convert.ToBase64String(System.Text.Encoding.UTF8.GetBytes
("username:password")));
            using (Stream s = request.GetRequestStream())
            {
                data.WriteTo(s);
            }
            data.Close();

            try
            {
                // use the request object to get to the response
                WebResponse response = request.GetResponse();

                if (response != null)
                {
                    StreamReader sr = new StreamReader
(response.GetResponseStream());
                    string result = sr.ReadToEnd();
                }
            }
            catch (WebException exception)
            {
                HttpWebResponse httpResponse = (HttpWebResponse)
exception.Response;

            }
        }


Exception and response details:

CharacterSet    utf-8
ContentEncoding
ContentLength   183
ContentType     application/xml; charset=utf-8
Cookies {System.Net.CookieCollection}
Headers {Status: 403 Forbidden
Pragma: no-cache
Vary: Accept-Encoding
Connection: close
Content-Length: 183
Cache-Control: no-cache, no-store, must-revalidate, pre-check=0, post-
check=0
Content-Type: application/xml; charset=utf-8
Date: Fri, 05 Dec 2008 15:26:28 GMT
Expires: Tue, 31 Mar 1981 05:00:00 GMT
Last-Modified: Fri, 05 Dec 2008 15:26:28 GMT
Set-Cookie:
_twitter_sess=BAh7BzoHaWQiJTgxZmIyODE1ZjY3MGI3YjRiOGE1MmFkODJmNjhlOGQwIgpm
%250AbGFzaElDOidBY3Rpb25Db250cm9sbGVyOjpGbGFzaDo6Rmxhc2hIYXNoewAG
%250AOgpAdXNlZHsA--b336ca8846bc144106c5160724c82d54b2bfe824;
domain=.twitter.com; path=/
Server: hi

System.Net.WebHeaderCollection
IsMutuallyAuthenticated FALSE
LastModified    {12/5/2008 9:26:28 AM}
Method  POST
ProtocolVersion {1.1}
ResponseUri     {http://twitter.com/account/update_profile_image.xml}
Server  hi
StatusCode      Forbidden
StatusDescription       Forbidden

ExceptionStatus ProtocolError