You can pass the usual parameters to $form->inputs, which you will go to $form->input.
For example, if you want to configure field2below, you make the field name with the key and an array of parameters a value:
echo $form->inputs(array(
'field1',
'field2' => array(
'label' => 'Date and time',
'type' => 'datetime',
'dateFormat' => 'DMY',
'minYear' => date('Y') - 1,
'maxYear' => date('Y'),
'empty' => true,
),
'field3',
));