/**
  * Filter store column
  *
  * @param Esendex_Sms_Model_Resource_Trigger_Collection $collection
  * @param Mage_Adminhtml_Block_Widget_Grid_Column $column
  * @return self
  */
 protected function _filterStoreCondition(Esendex_Sms_Model_Resource_Trigger_Collection $collection, Mage_Adminhtml_Block_Widget_Grid_Column $column)
 {
     if (!($value = $column->getFilter()->getValue())) {
         return;
     }
     $collection->addStoreFilter($value);
     return $this;
 }