Fehler nach dem Update

: Column not found: 1054 Unknown column post.username in order clause']Sun, 13 Dec 2015 10:29:06 +0000
Message: Could not execute prepared statement: SQLSTATE[42S22]: Column not found: 1054 Unknown column 'post.username' in 'order clause'
File: /var/www/html/forum/wcf/lib/system/database/statement/PreparedStatement.class.php (100)
PHP version: 5.5.9-1ubuntu4.14
WCF version: 2.0.13 (Maelstrom)
Request URI: /forum/index.php/Thread/364-Problem/?postID=1871
Referrer: 
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Firefox/38.0
Information: "<b>sql type:<\/b> wcf\\system\\database\\MySQLDatabase<br \/><b>sql error:<\/b> Unknown column 'post.username' in 'order clause'<br \/><b>sql error number:<\/b> 42S22<br \/><b>sql version:<\/b> 5.5.46-0ubuntu0.14.04.2<br \/><b>sql query:<\/b> SELECT  user.username as username, userList.userID as userID, userList.Counter as Counter FROM (SELECT post.userID, COUNT(*) as Counter\n\t\t\tFROM\twbb1_post post\n            WHERE post.threadID = ? AND post.isDeleted = 0 AND post.isDisabled = 0 GROUP BY post.userID) userList\n\t\t\tLEFT JOIN wcf1_user user\n\t\t\tON user.userID = userList.userID\n            ORDER BY Counter DESC, post.username DESC<br \/><b>sql query parameter 0:<\/b>364<br \/>"
Stacktrace: 
  #0 /var/www/html/forum/lib/data/post/WhoWrite.class.php(70): wcf\system\database\statement\PreparedStatement->execute(Array)
  #1 /var/www/html/forum/lib/system/event/listener/WhoWriteInThreadListener.class.php(24): wbb\data\post\WhoWrite::createArray('364')
  #2 /var/www/html/forum/wcf/lib/system/event/EventHandler.class.php(189): wbb\system\event\listener\WhoWriteInThreadListener->execute(Object(wbb\page\ThreadPage), 'wbb\page\Thread...', 'assignVariables')
  #3 /var/www/html/forum/wcf/lib/page/AbstractPage.class.php(113): wcf\system\event\EventHandler->fireAction(Object(wbb\page\ThreadPage), 'assignVariables')
  #4 /var/www/html/forum/wcf/lib/page/MultipleLinkPage.class.php(211): wcf\page\AbstractPage->assignVariables()
  #5 /var/www/html/forum/lib/page/ThreadPage.class.php(281): wcf\page\MultipleLinkPage->assignVariables()
  #6 /var/www/html/forum/wcf/lib/page/AbstractPage.class.php(182): wbb\page\ThreadPage->assignVariables()
  #7 /var/www/html/forum/wcf/lib/page/AbstractPage.class.php(86): wcf\page\AbstractPage->show()
  #8 /var/www/html/forum/wcf/lib/system/request/Request.class.php(58): wcf\page\AbstractPage->__run()
  #9 /var/www/html/forum/wcf/lib/system/request/RequestHandler.class.php(108): wcf\system\request\Request->execute()
  #10 /var/www/html/forum/index.php(10): wcf\system\request\RequestHandler->handle('wbb')
  #11 {main}