Problem with some POST data

[eluser]Alhazred[/eluser]
Here is the form code, I've left only one field, it doesn't work anyway

Code:

<?php
$attributes = array('id' => 'moduserdata');
echo form_open(base_url('users/mod_pers_data_act'), $attributes);
?>
<input type='text' id='nome' name='nome' value="<?php echo $this->session->userdata('nome') ?>" />
<input type='submit' name='submit' value='<?php echo lang('crd_form_confirm_btn') ?>'/>
</form>

The controller's function is

Code:

public function mod_pers_data_act()
{
echo $_POST['nome']; //prints an error for missing index
echo $this->input->post('nome'); //prints nothing
echo "blabla"; //this is printed
}