/**
  * Set a field in this model as a gems unique user id
  *
  * @param \MUtil_Model_DatabaseModelAbstract $model
  * @param string $idField Field that uses global id.
  */
 public function setAsGemsUserId(\MUtil_Model_DatabaseModelAbstract $model, $idField)
 {
     // Make sure field is added to save when not there
     $model->setAutoSave($idField);
     // Make sure the fields get a userid when empty
     $model->setOnSave($idField, array($this, 'createGemsUserId'));
 }