I set this zend form element radio:
//nationality
$this->addElement('radio', 'nationality', array('label' => 'F_NATIONALITY', 'separator' => ' ', 'label_class' => 'l_radio', 'required' => true));
$this->nationality->addMultiOption('italian', 'F_NATIONALITY_IT');
$this->nationality->addMultiOption('foreign', 'F_NATIONALITY_FO');
$this->nationality->addValidator('NotEmpty');
and this is the output:

what you do not understand is why I can not show the error message even if I set the attribute 'required' validator and 'NotEmpty'?
Thanks
Errorsdecorator. Tryvar_dump($this->nationality->getDecorators());and see what that returns. - drew010