when I navigate to http://mysite.com/admin, the browser returns the redirect error message.

this is the message that I get in firefox

" The page isn't redirecting properly

Firefox has detected that the server is redirecting the request for this address in a way that will never complete.

This problem can sometimes be caused by disabling or refusing to accept cookies.

"

but any params in the url returns just fine. like mysite.com/admin/abc returns the correct view.

route::get('admin', function() { .. }) 
or 
route::group(array('prefix' => 'admin','before'=>array('auth')), function() { .... }

both route ends up in redirect loop.

[note:] I haven't added any new functions or altered configurations in laravel bootstrap files. and my laravel version is 4.2, tested in chrome and firefox. any thoughts ?