Zend-Adding/Appending an element in a control in block

$form->submit->setDecorators(

 array(
             'ViewHelper',
              array(
                   array('data'=>'Html Tag' ),
                   array('placement'=>Zend_Form_Decorator_Abstract::PREPEND),
                    'tag'=>'span',
                    'class'=>'wp_submit'
                      ),
               array(
                    array(array('data'=>'Html Tag')),
                    array('tag'=>'span','class'=>'newspan')
                      )
        )

)