login.php

$s = new Savant3();

$f = $s->form('login');
$f->depends('email_addr', 'password');
$f->addValidation('email_addr', new Form_Validation('email', 'Please enter a valid email address'));
$f->addValidation('pass_confirm', new Form_Validation('confirm', 'Please confirm your password', array('against' => $f->password)));
 
if ($f->isSubmit() && $f->validate()) {
    // handle login
}