$daten = AttributeType::getByHandle('date');
        $eventthru = CollectionAttributeKey::getByHandle('event_thru');
        if (!is_object($eventthru)) {
            CollectionAttributeKey::add(
                $daten,
                array(
                    'akHandle' => 'event_thru',
                    'akName' => t('End Date'),
                    'akIsSearchable' => '1',
                    'akIsSearchableIndexed' => '1',
                    'akDateDisplayMode' => 'date',
                ),
                $pkg
            )->setAttributeSet($evset);
        }