Laravel: lang file in subfolder

I want to "multilocalize" my Laravel project.

I made my directory structure like this:

lang
- en
 - front
  - contact.php
-footer.php

And I built my footer like this:

{{ link_to('/', trans('footer.frontpage'))}}

It works perfectly, but when I want localize the other blade pages, for example the contact us page like this:

@lang('front.contact.name')

or this:

{{ __('front.contact.name') }}

or this:

{{ trans('front.contact.name') }}

I only got back on the page:

front.contact.name

What's the problem?