anchor.diff:      append_params(TypeBin, Disp#sip_hdr_disposition.params);
   
   %% 20.12 Content-Encoding
  +%% http://tools.ietf.org/html/rfc3261#section-20.12
   process(pn, <<"e">>, _Ignore) -> 'content-encoding';
   process(fn, 'content-encoding', _Ignore) -> <<"Content-Encoding">>;
   process(p, 'content-encoding', Bin) ->
  
positive.code:     format_address(Addr);
  
  %% 20.11 Content-Disposition
  process(fn, 'content-disposition', _Ignore) -> <<"Content-Disposition">>;
  process(p, 'content-disposition', Bin) ->
      {TypeBin, Rest} = sip_binary:parse_token(Bin),
  
negative.code:             Port -> <<Bin/binary, ?SP, Host/binary, ?HCOLON, (sip_binary:integer_to_binary(Port))/binary>>
          end,
      append_params(Bin2, Via#sip_hdr_via.params);
  
  
  %% ....
  