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='54.87.112.248') WHERE t.threadid = '6797'
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: 29.03.2017 @ 19:07
Script: /thread.php?threadid=6797&goto=lastpost&sid=ed35f48bdb6da6503bc80e12d6284873
Referer: