Missing controller

You are seeing this error because controller EX-SystemController could not be found.

Notice: this error is being rendered by the app/views/errors/missing_controller.thtml view file, a user-customizable error page for handling invalid controller dispatches.

Fatal: Unable to load controller EX-SystemController

Fatal: Create Class:

<?php
class EX-SystemController extends AppController
{
    var $name = 'EX-System';
}
?>

in file : app/controllers/e_x-system_controller.php