add in WorldSession.cpp just below all code
change WorldSession::HandleArenaTeamInviteAcceptOpcode accordingly to the names of all unresolved externals so you have 18 funcs

void WorldSession::HandleArenaTeamInviteAcceptOpcode(WorldPacket& recv_data)
    {
            sLog.outError( "WORLD: received unhandled opcode %s (0x%.4X)",
                LookupName(recv_data.GetOpcode(), g_worldOpcodeNames),
                recv_data.GetOpcode());
    }