Routing with multilanguage

[eluser]0v3rth3d4wn[/eluser]
Hi! I have the following issue. It is a silly one and I read all about it but couldn't find a way to do it. I totally blocked.

I want to route http://www.mysite.com/en/category/1 to use http://www.mysite.com/en/category/index/1 but it needs to be done for all the languages I'm gonna be using. Here is what I last tried and still didn't got it to work:

Code:

$route['(bg|eng)/category/(:num)'] = "$1/category/index/$3";

But still not working. Any ideas? I think i'm not using right the $1 and the $3...