/**
  * Checks if member is registered in the core,
  * @return true if member_id is registered, false otherwise
  */
 private function memberIdCheck($member_id_to_check)
 {
     $student = new Core_Model_Member_Student();
     $student->setMember_id($member_id_to_check);
     $member_id_exists = $student->memberIdCheck();
     if (!$member_id_exists) {
         //Zend_Registryget('logger')->debug(
         //'Member with member_id : ' . $member_id_to_check .
         //' is not registered in CORE');
     }
     return $member_id_exists;
 }