title: QNetworkReply::UnknownNetworkError from QNetworkAccessManager::get when requesting https with a password protected proxy server
body: <p>I'm having a problem with QNetworkAccessManager. Here is some brief description of what I am doing:</p>
  
  <pre><code>QNetworkAccessManager* manager = new QNetworkAccessManager(this);
  manager-&gt;setProxy(proxy);
  QUrl url("https://www.example.com");
  QNetworkRequest request(url);
  manager-&gt;get(request);
  </code></pre>
  
  <p>In order to test the code on a password protected proxy server I used Polipo. When setting up a password for the server and using a NON-https url (http://www.example.com) I normally get proxyAuthenticationRequired() signal emitted. However, with https urls I don't have that signal (or sslErrors() signal) emitted and finished() signal is emitted with reply->error() equal to QNetworkReply::UnknownNetworkError. I'm sure that this is not a Polipo issue because the browsers are still asking for username/password for proxy server although in case of incorrect credentials they don't say "proxy authentication failed" like for http urls, just say that page cannot be opened. So I need to know how to configure qt classes or its ssl classes to ask for authentication and fix this problem.</p>
  
  <p>I'm using Qt 4.5.2.</p>
  
  <p>Thanks!</p>