anchor.diff:      OldSipState = State#state.sipstate,
       case NewSipState of
   	OldSipState ->
  -	    logger:log(debug, "~s: Evaluated ~p ~s (in response to ~s ~s). Remaining in state '~p', action '~p'.",
  +	    logger:log(debug, "~s: Evaluated '~p ~s' (in response to ~s ~s). Remaining in state '~p', action '~p'.",
   		       [LogTag, Status, Reason, Method, sipurl:print(URI), OldSipState, BranchAction]),
   	    %% Update response so that we report exactly this response to our parent and not any previous
   	    %% (for example, report a previous 183 instead of this new one)
   	    NewState = State#state{response=Response},
   	    NewState;
   	_ ->
  -	    logger:log(debug, "~s: Evaluated ~p ~s (in response to ~s ~s). Changing state from '~p' "
  +	    logger:log(debug, "~s: Evaluated '~p ~s' (in response to ~s ~s). Changing state from '~p' "
   		       "to '~p', action '~p'.", [LogTag, Status, Reason, Method, sipurl:print(URI),
   						 OldSipState, NewSipState, BranchAction]),
   	    NewState = State#state{sipstate=NewSipState, response=Response},
  
positive.code:     %% State has not changed
      {State, BranchAction};
  act_on_new_sipstate(OldSipState, NewSipState, BranchAction, State)
    when is_atom(OldSipState), is_atom(NewSipState),  is_atom(BranchAction),
         BranchAction == ignore; BranchAction == tell_parent,
         is_record(State, state) ->
      %% State has changed
  
negative.code: 
  
  received_response_state_machine(Method, Status, trying) when Status >= 300, Status =< 599 ->
      logger:log(debug, "UAC decision: Received 3/4/5xx response ~p to ~s when in state 'trying', " ++
  	       "entering state 'completed' and telling parent", [Status, Method]),
      {tell_parent, completed};
  received_response_state_machine("INVITE", Status, calling) when Status >= 300, Status =< 599 ->
      logger:log(debug, "UAC decision: Received 3/4/5xx response ~p to INVITE when in state 'calling', " ++
  	       "entering state 'completed' and telling parent", [Status]),
      {tell_parent, completed};
  received_response_state_machine(Method, Status, proceeding) when Status >= 300, Status =< 599 ->
      logger:log(debug, "UAC decision: Received 3/4/5xx response ~p to ~s when in state 'proceeding', " ++
  	       "entering state 'completed' and telling parent", [Status, Method]),
      {tell_parent, completed};
  received_response_state_machine(Method, Status, State) when Status >= 300, Status =< 599 ->
      logger:log(debug, "UAC decision: Received 3/4/5xx response ~p to ~s when in state '~p', " ++
  	       "ignoring", [Status, Method, State]),
      {ignore, State};
  
  