HttpWebRequest and HTTPS on iOS

I have some dynamic file downloading code that works great on all platforms except when using an HTTPS URL on iOS.

I am using HttpWebRequest because these resources are being loaded in a background thread (and you can't use WWW from another thread.)

On all the other platforms I have tried, Windows/OSX/Android, using an HTTPS URL works fine. On iOS, I get an exception with "ConnectFailure" as the message...

The code used is below:

 private void LoadRemoteImages( List<string> in_aImageURLs )
 {
     try
     {
         //We only support JPG or PNG
         foreach( string l_strTextureURL in in_aImageURLs )
         {
             try
             {
                 //We only support JPG or PNG
                 string l_strExtension = Path.GetExtension( l_strTextureURL ).ToLower();
 
                 if( ( l_strExtension != ".jpg" ) && ( l_strExtension != ".png" ) )
                 {
                     Debug.LogError( "Unsupported or missing extension found in LoadRemoteImages, the extension was: " + l_strExtension );
                     continue;
                 }
 
                 Debug.Log( "Attempting to download: " + l_strTextureURL );
 
                 HttpWebRequest request = (HttpWebRequest)WebRequest.Create( l_strTextureURL );
                 request.Method = WebRequestMethods.Http.Get;
 
                 HttpWebResponse response = (HttpWebResponse)request.GetResponse();
 
                 /*
                     Check that the remote file was found. The ContentType
                     check is performed since a request for a non-existent
                     image file might be redirected to a 404-page, which would
                     yield the StatusCode "OK", even though the image was not
                     found.
                 */
                 if( ( response.StatusCode == HttpStatusCode.OK || response.StatusCode == HttpStatusCode.Moved || response.StatusCode == HttpStatusCode.Redirect ) && response.ContentType.StartsWith( "image", StringComparison.OrdinalIgnoreCase ) )
                 {
                     string l_strLocalFilename = m_strApplicationDataPath + "/" + _Utility.HashStringToFilename( l_strTextureURL );
 
                     //Download it
                     using( Stream inputStream = response.GetResponseStream() )
                     using( Stream outputStream = File.OpenWrite( l_strLocalFilename ) )
                     {
                         byte[] buffer = new byte[ 16384 ];
                         int bytesRead;
 
                         do
                         {
                             bytesRead = inputStream.Read( buffer, 0, buffer.Length );
                             outputStream.Write( buffer, 0, bytesRead );
                         }
                         while( bytesRead != 0 );
                     }
                 }
                 else
                 {
                     Debug.Log( "Bad response from web server, file was not downloaded..." );
                 }
             }
             catch( WebException l_oException )
             {
                 Debug.LogError( "WebException status -> " + l_oException.Status.ToString() );
 
                 if( l_oException.Response != null )
                 {
                     Debug.LogError( "WebException Response -> " + l_oException.Response.ToString() );
                 }
                 else
                 {
                     Debug.LogError( "WebException Response is NULL" );
                 }
 
                 Debug.LogError( "WebException -> " + l_oException.ToString() );
             }
             catch( Exception l_oException )
             {
                 Debug.LogError( "Exception caught try to download remote image: " + l_strTextureURL + " the exception was -> " + l_oException.Message);
             }
         }
     }
     finally
     {
         m_bLoaderThreadStillWorking = false;
     }
 }

Has anyone successfully used HttpWebRequest over HTTPS on iOS?

Cheers :)