public function getFieldValidationOptions()
 {
     $fields = parent::getFieldValidationOptions();
     $validEmailFields = EditableEmailField::get()->filter(array('ParentID' => (int) $this->ParentID))->exclude(array('ID' => (int) $this->ID));
     $fields->add(DropdownField::create('EqualToID', _t('EditableConfirmEmailField.EQUALTO', 'Must be equal to'), $validEmailFields->map('ID', 'Title'), $this->EqualToID)->setEmptyString('- select -'));
     return $fields;
 }