Apache proxypass + CI 2.1.3

[eluser]noideawhattotypehere[/eluser]
Hi there.
I've got a small problem using my custom cms built with codeigniter. Im currently developing it in my local enviroment. Linux mint 14/xampp 1.8.1
My pages are in this format:
http://localhost/cms/front/[id] where id = id of site, eg.
http://localhost/cms/front/1 - first service
http://localhost/cms/front/2 - some other service
Basically what i want is to proxy it to some decent urls using virtualhosts, lets say all used domains here are pointing to my localhost server (i changed hosts file), here is my httpd-vhosts.conf:

Code:

<VirtualHost www.virtualhost.pl>
    ProxyPass / http://localhost/cms/front/1/
    ProxyPassReverse / http://localhost/cms/front/1/
    ServerName virtualhost.pl
    ServerAlias www.virtualhost.pl
</VirtualHost>

It works, when i visit www.virtualhost.pl it shows my page, but the problem is: codeigniter log shows this:
ERROR - 2013-08-09 09:46:23 --> 404 Page Not Found --> front/1
Any idea what's wrong? I'm not so experienced in using all these apache options so probably something is wrong with my virtualhost entry. Strange that it works in browser but CI logs 404 error.
I'd appreciate any help, thanks in advance.

EDIT:
Additional info:
If i change
ProxyPass / http://localhost/cms/front/1/
ProxyPassReverse / http://localhost/cms/front/1/
to
ProxyPass / http://localhost/cms/front/1
ProxyPassReverse / http://localhost/cms/front/1
(see, no '/')
it throws this:
ERROR - 2013-08-09 10:24:01 --> 404 Page Not Found --> front/1favicon.ico

[eluser]noideawhattotypehere[/eluser]
Nevermind, adding

Code:

<link rel="icon" href="" type="image/gif">

Fixes the problem.