Custom routes not working

I'm trying to build a custom route. I'd like to map /account-overview to the AccountOverview class method processRequest() so I entered this as my /application/config/routes.php:


$route['default_controller'] = 'accountOverview/processRequest';   // just to test the controller when it would not come up
$route['404_override'] = '';
$route['translate_uri_dashes'] = FALSE;
$route['account-overview'] = 'accountOverview/processRequest';


The page comes up when I enter just localhost - so the page itself is functional but when I try the /account-overview URL I get NOT FOUND. I've tried adding a second part to the URL like /account-overview/page and mapping that but all I get is 404 NOT FOUND. I even tried using /accountOverview/processRequest and still got NOT FOUND. What is wrong? This is the most basic function of a framework if this doesn't work then I can't use codeIgniter. How can I execute class AccountOverview method processRequest  ??? Ideally with a friendly URL ???

I've checked and there are no .htaccess files anywhere that could mess with the URL. I do not have a _remap function anywhere. There's nothing in the log files. How do I debug the framework itself?The bug would be _parse_routes of /system/core/Router.php - I can start debugging from there. Something tells me i'm going to extend yet another /system/core class. I'd prefer not to. Any ideas?