/**
  * tearDown
  */
 public function tearDown()
 {
     // purge
     $backend = new Tinebase_PersistentFilter_Backend_Sql();
     $toDeleteIds = $backend->search(new Tinebase_Model_PersistentFilterFilter(array(array('field' => 'name', 'operator' => 'startswith', 'value' => 'PHPUnit'))), NULL, TRUE);
     $backend->delete($toDeleteIds);
 }