Private function and Custom form validation

[eluser]InsiteFX[/eluser]

Code:

array(
     'field' => 'check_terms',
     'label' => 'Terms of service',
     'rules' => 'callback__check_terms' // double underscore
)

Code:

public function _check_terms($terms=0){
     if ($terms != 'agree')
     {
          $this->form_validation->set_message('_check_terms', 'The terms of service must be read and agreed to before continuing.'); // according to CroNiX
          return FALSE;
     }
     else
     {
          return TRUE;
     }
}