https - Windows Phone 8 HttpClient 上的 HTTPS 支持

Question

我正在尝试使用 Nuget Http 客户端库：

 HttpRequestMessage request = new HttpRequestMessage(HttpMethod.Get, url);
    request.Headers.Add("UserAgent", "Windows 8 app client");

    HttpClient client = new HttpClient();
    HttpResponseMessage response = await client.SendAsync(request, HttpCompletionOption.ResponseHeadersRead);

    if (response.StatusCode == HttpStatusCode.OK)
      return await response.Content.ReadAsStringAsync();
    else
     throw new Exception("Error connecting to " + url +" ! Status: " + response.StatusCode);

当我向具有自签名证书的站点发出 https 请求时，我收到 404 错误。如何设置标志以允许客户端中的 SSL 证书无效？