Worldserver auth

Sorry for my English.
I start backporting TrinityCore for classic WoW. I change some network logic and now MangosZero and forked TrinityCore send to client similar packets. But client close connection after receiving SMSG_ADDON_INFO and SMSG_AUTH_RESPONSE. I cant find reason by learning mangosZero code. May difference between ace and boost be the reason? What can cause this?
Maybe this forum is wrong place for asking this. Thank you.

[ATTACH]1636._xfImport[/ATTACH]

Solved. Classic WOW have different headers format, and different encryption algorhytm.