action not allowed on form validation

Thanks! You are right, it works if i set csfr on false. But I need to have it set on TRUE. So i googled about it and tried to make hidden input like this

PHP Code:

$hidden = array($this->security->get_csrf_token_name() => $this->security->get_csrf_hash());
echo form_open('pages/Login', '', $hidden); 


and

PHP Code:

<div style="display:none">
<input type="hidden" name="<?php echo $this->security->get_csrf_token_name(); ?>" value="<?php echo $this->security->get_csrf_hash();?>" />
</div> 


but nothing of above solved a problem.

Do you have any suggestions how to make it work? I can't be the only one with this kind of problem?