roundware/?operation=request_stream generates DeprecationWarning

lib/python2.7/site-packages/django/http/response.py:330: DeprecationWarning: Using mimetype keyword argument is deprecated, use content_type instead
  super(HttpResponse, self).__init__(*args, **kwargs)

[13/Jun/2014 19:25:54] "GET /roundware/?operation=request_stream&session_id=2891 HTTP/1.1" 200 62