Example (xor decoding already applied), start of game server interaction.
Legend:
  < - packet from client to server.
  > - packet from server to client.
XXX: - packet size.

Code:
1) < 265: 0e 3f 03 00 00 09 ......
 2) >  23: 2e 01 fd 14 41 f3 8f b2 96 f6 01 00 00 00 01 00 00 00 00 4a aa 61 1a
 3) <  41: 5d 6d 00 61 00 72 00 32 00 33 00 75 00 6e 00 69 00 78 00 00 00 4c 43 0f 00 a4 13 00 00 4c 43 0f 00 7c 51 68 4f 01 00 00 00
 4) > 311: 09 01 00 00 00 07 00 00 00 00 66.........
 5) <  19: 12 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 6) >   3: 73 00 01
 7) > 223: 0b 66 00 67 00 73 00 68 0........
 8) <   3: 03 4d 00
 9) <   3: 03 06 00
10) > 163: fe 22 00 09 00 00 00 01 00 .......
11) < 105: 58 23 92 90 4d 18 30 b5 7c .......
Here you can see (by line):
1) As it was in CT1 - ProtocolVersion packet, with protocol version 831.
2) KeyPacket from server, new token - 4a aa 61 1a, at end of this packet.
3) There should be AuthLogin, but it has different packet code.
5) CharSelected packet - code was not changed (tested by many passes).
8, 9) ExPacket - codes are different again.

But after relogin the traffic is changed somehow:

Code:
< 265: 0e 3f 03 00 00 09 .....
>  23: 2e 01 9d 26 15 9b 0e d0 21 f5 01 00 00 00 01 00 00 00 00 93 5b 62 59
<  43: 7b 6c 00 6f 00 6c 00 6a 00 6f 00 69 00 6e 00 65 00 72 00 39 00 00 00 84 54 0f 00 a6 1e 00 00 84 54 0f 00 bc 27 bd 03 01 00 00 00
> 311: 09 01 00 00 00 07 00 00 0....
<  19: 12 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>   3: 73 00 01
> 221: 0b 62 00 75 00 62 00 75 00 .....
<   3: 42 1b 00
<   3: 42 30 00
< 105: 72 23 92 90 4d 18 30 b5 7c 96 .....
> 163: fe 22 00 09 00 00 00 01 00 00 00 67 .....

As you can see packet codes from client were changed.