SQL-DATABASE ERROR

Database error in WoltLab Burning Board (2.3.6): Invalid SQL: SELECT t.*, v.id AS isvoted FROM bb1_threads t LEFT JOIN bb1_votes v ON (v.id=t.threadid AND v.votemode=2 AND v.ipaddress='54.166.238.61') WHERE t.threadid = '6841'
mysql error: Unknown column 'v.votemode' in 'on clause'
mysql error number: 1054
mysql version: 5.1.73-log
php version: 5.6.30
Date: 30.04.2017 @ 12:57
Script: /thread.php?goto=lastpost&threadid=6841&sid=d54a6afa9d95ab0d15f925f0068ad1db
Referer: