Authorization facebook (require login) with cakephp cause looping auth key session

Hi, im developing facebook iframe application with cakephp.
My problem is i need facebook authorization soon as user visiting homepage.
i'm put this code $user = $this->facebook->require_login(); in app_controller before filter method, seems its working with user authorization.

but after user authorize my application is leaving facebook frame and go to normal page (not inside facebook), and i'm seeing this on address bar "auth_token=f754dc2ed39b5e2b93f11a6e648f1517&installed=1".

then when im click link to another page on my application seems that auth_token key is looping on address bar.

how can i fix this?