It works fine in the current Git version you can get from:
https://github.com/rathena/rathena
You can find the bonus in pc.c in function pc_checkbaselevelup:
} else if( (sd->class_&MAPID_BASEMASK) == MAPID_TAEKWON ) {
sc_start(&sd->bl,&sd->bl,status_skill2sc(AL_INCAGI),100,10,600000);
sc_start(&sd->bl,&sd->bl,status_skill2sc(AL_BLESSING),100,10,600000);
}