Somehow i managed to solve my problem.
Try to go to your rathena/src/custom/defines_pre.hpp and open it with notepad.
and just under this two lines:
#ifndef CONFIG_CUSTOM_DEFINES_PRE_HPP
#define CONFIG_CUSTOM_DEFINES_PRE_HPP
add:
#define PACKETVER YYYYMMDD <------ your client
then recompile. This solved my problem.