roles

I have these roles defined:

<?php
return array(
    'sponsor'=> array(
        'sponsor_home',
    	'sponsor_dashboard',
    ),
	'guest'=> array(
		'login',
		'login/authenticate',
		'sponsor_login',
		'sponsor_login/authenticate'
	),
	'users' => array(
		'home',
		'dashboard',
		'dashboard/default',
	)
);

When I set $userRole = 'guest'; and when I call sponsor_login, I was able to see login page. But when I changed $userRole = 'sponsor' and called same sponsor_login page, page says The page isn't redirecting properly. What's wrong here. As per my requirement. It should be redirected to sponsor_home page. Could you please suggest something.