Exception in sms telerivet submissions

[ukanga]

  File "/.../srv/formhub-ec2/project_env/local/lib/python2.7/site-packages/django/core/handlers/base.py", line 115, in get_response
    response = callback(request, *callback_args, **callback_kwargs)

  File "/.../srv/formhub-ec2/project_env/local/lib/python2.7/site-packages/django/views/decorators/csrf.py", line 77, in wrapped_view
    return view_func(*args, **kwargs)

  File "/.../srv/formhub-ec2/formhub/sms_support/providers/__init__.py", line 64, in import_submission_for_form
    .get('imp_form', unknown_service)(request, username, None)

  File "/.../srv/formhub-ec2/project_env/local/lib/python2.7/site-packages/django/views/decorators/http.py", line 41, in inner
    return func(request, *args, **kwargs)

  File "/.../srv/formhub-ec2/project_env/local/lib/python2.7/site-packages/django/views/decorators/csrf.py", line 77, in wrapped_view
    return view_func(*args, **kwargs)

  File "/.../srv/formhub-ec2/formhub/sms_support/providers/telerivet.py", line 89, in import_submission_for_form
    id_string=id_string)

  File "/.../srv/formhub-ec2/formhub/sms_support/providers/telerivet.py", line 105, in process_message_for_telerivet
    return get_response(response)

  File "/.../srv/formhub-ec2/formhub/sms_support/providers/telerivet.py", line 54, in get_response
    message = _(u"[ERROR] %s") % message

UnboundLocalError: local variable 'message' referenced before assignment

[pld]

looks like we could use a test around this.