[TYPO3-mvc] Problem with Frontend Autopopulation of Property value

[Daniel Kemper]

Hey folks,

i have a problem with my extension.

I extend the fe_groups table with a column called event_storage. The event 
storage ist a relation to the pages table.
If i´m logged in into the backend my extension is working fine. I get the 
values of the event_storage field. But without the backend login my i can´t 
get the value of the event_storage field. (my own fe_group field) I can´t 
see the property in the "_cleanProperties".

class Tx_MyExtKey_Domain_Model_FeUserGroup extends 
Tx_Extbase_Domain_Model_FrontendUserGroup
{
 /**
  * @var integer
  */
 protected $eventStorage = 0;

 /**
  *
  * @return mixed $eventStorage;
  */
 public function getEventStorage()
 {
  return $this->eventStorage;
 }

 /**
  * sets the event storage
  * @param string $eventStorage;
  * @return void;
  */
 public function setEventStorage($eventStorage)
 {
  $this->eventStorage = $eventStorage;
 }
}

In the ext_tables.php i added this parts.

$tempColumns = Array (
      "event_storage" => Array (
            "exclude" => 1,
            "label" => 
"LLL:EXT:myextkey/Resources/Private/Language/locallang_db.xml:fe_groups.event_storage",
   'config' => array (
    'type' => 'group',
    'internal_type' => 'db',
    'allowed' => 'pages',
    'size' => 5,
    'minitems' => 0,
    'maxitems' => 5,
   )
      ),
);

t3lib_extMgm::addTCAcolumns("fe_groups",$tempColumns,0);
t3lib_extMgm::addToAllTCAtypes("fe_groups","--div--Tab,event_storage;;;;1-1-1");
t3lib_div::loadTCA("fe_groups");

I know that there is a problem with ext_tables.php and the frontend module. 
But if i move it to the ext_localconf.php the problem is the same. I updated 
to the newest version.

Has anyone an idea?

Thanks.

Daniel Kemper