Route 404 Over Ride sub directory issue

Hello,

In codeingiter application/config/routes.php

I would like to know if possible to have sub directory / name

controllers > error > Not_found.php

PHP Code:

$route['404_override'] = 'error/not_found'; 


But it only seems to work with code below.

PHP Code:

$route['404_override'] = 'not_found'; 


I need it to be able to get from sub directory.

Is there any way to change it?

There's only one rule - please don't tell anyone to go and read the manual.  Sometimes the manual just SUCKS!