So one of the best parts about the new Silverlight 4 beta is that they finally implemented the big missing feature of the networking stack - Network Credentials!

In the below I have a working request setup, but for some reason I get a "security error" when the request comes back - is this because twitter.com rejected my api call or something that I'm missing in code?

It might be good to point out that when I watch this code execute via fiddler it shows that the xml file for cross domain is pulled down successfully, but that is the last request shown by fiddler ...

public void RequestTimelineFromTwitterAPI()
        {
               WebRequest.RegisterPrefix("https://", System.Net.Browser.WebRequestCreator.ClientHttp);

               WebClient myService = new WebClient();
               myService.AllowReadStreamBuffering = true;
               myService.UseDefaultCredentials = false;
               myService.Credentials = new NetworkCredential("username", "password");
               myService.UseDefaultCredentials = false;

               myService.OpenReadCompleted += new OpenReadCompletedEventHandler(TimelineRequestCompleted);
               myService.OpenReadAsync(new Uri("https://twitter.com/statuses/friends_timeline.xml"));
        }

        public void TimelineRequestCompleted(object sender, System.Net.OpenReadCompletedEventArgs e)
        {
            //anytime I query for e.Result I get a security error
        }