This has to be set in the components section of main.php
'session' => array ( 'sessionName' => 'Site Access', ),
However I have noticed that the session name did not change until the main layout page (in the views/layouts/ folder) was loaded. And even then it only occurred after the main menu widget was called. Prior to that the session name was the PHP default. It was not changed when the site controller, the Controller class or any preceding scripts in the framework were executed.
I had to manually call session_name("name") and session_start() at the top of the main index page of the framework. Is this a reasonable solution? Does the framework have it wrong?