Evidently, PHP changed the way how objects work in the new 5.4 version. I noticed that I started to get these alot:

[21-Oct-2014 15:27:04 America/New_York] PHP Warning: Creating default object from empty value in /home/someuser/public_html/example.com/admin/attributes_controller.php on line 924

To "fix" this, I changed that particular line from this:

PHP Code:
if ($action == 'attributes_preview') {
  
$_GET['products_id'] = $products_filter;
  
$pInfo->products_id $products_filter;
  include(
DIR_WS_INCLUDES 'attributes_preview.php');
?> 
to this:

PHP Code:
if ($action == 'attributes_preview') {
  
$_GET['products_id'] = $products_filter;

  if (!isset(
$pInfo)) $pInfo = new stdClass();
  
$pInfo->products_id $products_filter;

  include(
DIR_WS_INCLUDES 'attributes_preview.php');
?> 
Hope this helps.