anchor.diff:         N == send_short_avp_length;
          N == send_zero_avp_length;
          N == send_invalid_avp_length;
  -       N == send_invalid_reject ->
  +       N == send_invalid_reject;
  +       N == send_unknown_short_mandatory ->
       Rec;
   answer(Rec, [], _) ->
       Rec.
  
positive.code:     io:format("~p: ~p~n", [T,P]).
  
  %% prepare/4
  
  prepare(Pkt, Caps, N, #group{client_dict0 = Dict0} = Group)
    when N == send_long_avp_length;
  
negative.code:                            data = <<17>>}]}
          = lists:last(Avps).
  
  %% Ditto, and point the AVP length past the end of the message. Expect
  %% 5014.
  send_unknown_short(Config) ->
      send_unknown_short(Config, false, ?INVALID_AVP_LENGTH).
  
  send_unknown_short(Config, M, RC) ->
      Req = ['ASR', {'AVP', [#diameter_avp{code = 999,
                                           is_mandatory = M,
                                           data = <<17>>}]}],
      ['ASA', _SessionId, {'Result-Code', RC} | Avps]
          = call(Config, Req),
      [#'diameter_base_Failed-AVP'{'AVP' = As}]
          = proplists:get_value('Failed-AVP', Avps),
      [#diameter_avp{code = 999,
                     is_mandatory = M,
                     data = <<17, _/binary>>}]  %% extra bits from padding
          = As.
  
  %% Ditto but set the M flag.
  send_unknown_mandatory(Config) ->
      Req = ['ASR', {'AVP', [#diameter_avp{code = 999,
  