anchor.diff:  
       %% Timestamp NOT present in 486 Busy Here
       autotest:mark(?LINE, "make_response/7 - 2.3"),
  -    [] = keylist:fetch("Timestamp", Response2#response.header),
  +    [] = keylist:fetch(timestamp, Response2#response.header),
   
       %% Content-Type NOT present in 486 Busy Here with empty body
       autotest:mark(?LINE, "make_response/7 - 2.4"),
  
positive.code:        is_list(ViaParameters), is_atom(Proto), is_record(Request, request) ->
      ReqHeader = Request#request.header,
      AnswerHeader1 = keylist:appendlist(keylist:copy(ReqHeader, [via, from, to, 'call-id', cseq,
  								'record-route', "Timestamp", 'content-type']),
  				       ExtraHeaders),
      %% PlaceHolderVia is an EXTRA Via with our hostname. We could do without this if
      %% we sent it with send_response() instead of send_proxy_response() but it is easier
  
negative.code:     %% The preservation of Timestamp headers into 100 Trying response is mandated by RFC 3261 8.2.6.1
      AnswerHeader5 = case Status of
  			100 -> AnswerHeader4;
  			_ -> keylist:delete(timestamp, AnswerHeader4)
  		    end,
      set_response_body(#response{status=Status, reason=Reason, header=AnswerHeader5}, Body).
  
  