Move into this thread function

Fri, 31 May 2013 16:08:04 +0000
Message: PHP notice in file C:\wamp\www\woltlab\lib\data\post\PostAction.class.php (1749): Trying to get property of non-object
File: C:\wamp\www\woltlab\wcf\lib\system\WCF.class.php (281)
PHP version: 5.4.3
WCF version: 2.0.0 Beta 1 (Maelstrom)
Request URI: /woltlab/index.php/AJAXProxy/?t=d8313e23069b207764964bac6b5c3c426fec8f4b
Referrer: http://localhost/woltlab/index.php/Thread/2-Ipsum-dolor/
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:21.0) Gecko/20100101 Firefox/21.0
Stacktrace: 
  #0 C:\wamp\www\woltlab\lib\data\post\PostAction.class.php(1749): wcf\system\WCF::handleError(8, 'Trying to get p...', 'C:\wamp\www\wol...', 1749, Array)
  #1 [internal function]: wbb\data\post\PostAction->moveToExistingThread()
  #2 C:\wamp\www\woltlab\wcf\lib\data\AbstractDatabaseObjectAction.class.php(171): call_user_func(Array)
  #3 C:\wamp\www\woltlab\wcf\lib\action\AJAXProxyAction.class.php(76): wcf\data\AbstractDatabaseObjectAction->executeAction()
  #4 C:\wamp\www\woltlab\wcf\lib\action\AJAXInvokeAction.class.php(96): wcf\action\AJAXProxyAction->invoke()
  #5 C:\wamp\www\woltlab\wcf\lib\action\AbstractAction.class.php(49): wcf\action\AJAXInvokeAction->execute()
  #6 C:\wamp\www\woltlab\wcf\lib\action\AJAXInvokeAction.class.php(63): wcf\action\AbstractAction->__run()
  #7 C:\wamp\www\woltlab\wcf\lib\system\request\Request.class.php(58): wcf\action\AJAXInvokeAction->__run()
  #8 C:\wamp\www\woltlab\wcf\lib\system\request\RequestHandler.class.php(93): wcf\system\request\Request->execute()
  #9 C:\wamp\www\woltlab\index.php(10): wcf\system\request\RequestHandler->handle('wbb')
  #10 {main}