anchor.diff:  
   process(f, 'reply-to', Addr) when is_record(Addr, sip_hdr_address) ->
       format_address(Addr);
  +
  +%% 20.32 Require
  +%% http://tools.ietf.org/html/rfc3261#section-20.32
  +process(fn, 'require', _Ignore) -> <<"Require">>;
  +process(p, 'require', Bin) ->
  +    {ExtBin, Rest} = sip_binary:parse_token(Bin),
  +    Ext = sip_binary:binary_to_existing_atom(sip_binary:to_lower(ExtBin)),
  +    parse_list('require', Ext, Rest);
  +
  +process(f, 'require', Ext) ->
  +    sip_binary:any_to_binary(Ext);
   
   %% .....
   process(pn, <<"v">>, _Ignore) -> 'via';
  
positive.code:                                    {'organization', <<"Boxes by Bob">>}, {'priority', <<"non-urgent">>},
                                     {'proxy-authenticate', <<"Digest realm=\"atlanta.com\"">>}, {'proxy-authorization', <<"Digest username=\"Alice\"">>},
                                     {'proxy-require', <<"foo">>}, {'record-route', <<"<sip:server10.biloxi.com;lr>">>},
                                     {'reply-to', <<"Bob <sip:bob@biloxi.com>">>},
  
  
                                     {'content-length', <<"5">>}, {'via', <<"SIP/2.0/UDP localhost">>},
  
negative.code:                                    {'x-custom-atom', 25},
                                     {'allow', <<"INVITE, ACK, CANCEL, OPTIONS, BYE">>},
                                     {'supported', <<"100rel">>}, {'unsupported', <<"bar, baz">>},
                                     {<<"X-Custom">>, <<"value">>}])),
  
       % Already parsed
  