My live site is running on 5.3.2-1ubuntu4.9. It uses apc. When I run the cron, it breaks right when it creates the helper class.
I tried creating the class using new, XenForo_Model::create, and by using one of the other models to create the helper class. Each way works on my local site but not on my live site.
No errors are showing up in the server error log.
This line also seemed to be causing a problem. When it was uncommented it caused php to crash before the class was loaded even though it is in that class:
$xfUserModel = XenForo_Model::create('Xenforo_Model_User'); $dwPsnUser->set('username', $xfUserModel->getUserById($ufvWithPsnUser['ufv_user_id'])['username']);