Laravel 4 Auth::attempt($userdata, false) authentication is still kept - authentication

Question

Recently I have decided to add a "remember me" feature to my Laravel 4 app.
Appropriate method with syntaxis was found:
Auth::attempt(array $credentials = array(), $remember = false)
This was adopted for my needs like so:
Auth::attempt($userdata, Input::has('remember'))
Application kept the Auth session, and the user was authenticated even after browser was closed.
Although, I have found out that now Laravel always keeps a user authenticated, no matter what state "remember" checkmark is.
I have tried to do:
Auth::attempt($userdata, false)
and
Auth::attempt($userdata,)
User was still authenticated across the browser sessions!!!
Now, since Auth::attempt($userdata) not keeping the auth session, I felt that whenever there is an indications of the second argument in Auth::attempt method, Laravel auto assumes it as "true".
Can anyone clarify that?
EDIT:
To make it a super clear to everyone, I will list the steps to recreate this behaviour:
Logout of the app Auth::logout();
Login again Auth::attempt($userdata, false)
Close and open the browser
Go to the app url.
Application is loaded authenticated
This is my first question here, so please, be patient with me :)

Answer 1

EDIT : OP made clear he called Auth::logout() properly, so answer is edited to include the "Real" answer.
Set lifetime value in app/config/session/php to 0 to make cookie clear on browser close.
Previous answer
This is the login method in Illuminate\Auth\Guard (Which is facaded to Auth) class, which is eventually called by Auth::attempt().
source : http://laravel.com/api/source-class-Illuminate.Auth.Guard.html#263-291
public function login(UserInterface $user, $remember = false)
{
$id = $user->getAuthIdentifier();
$this->session->put($this->getName(), $id);
// If the user should be permanently "remembered" by the application we will
// queue a permanent cookie that contains the encrypted copy of the user
// identifier. We will then decrypt this later to retrieve the users.
if ($remember)
{
$this->queuedCookies[] = $this->createRecaller($id);
}
// If we have an event dispatcher instance set we will fire an event so that
// any listeners will hook into the authentication events and run actions
// based on the login and logout events fired from the guard instances.
if (isset($this->events))
{
$this->events->fire('auth.login', array($user, $remember));
}
$this->setUser($user);
}
It is clear that even though the cookie is set when $remember is set to true, the cookie itself is not cleared when $remember is set to false or other non-truthy value.
The cookie is cleared when you call Auth::logout() function.