Laravel 4.1 on nginx routes error 404

Question

I am having troubles with the routes of laravel on a nginx Server. It shows a "404 not found" for all the routes, except for the default one, very similar to this problem: nginx configuration for Laravel 4

The solution to that problem:

server {

    listen  80;
    server_name sub.domain.com;
    set $root_path '/srv/www/htdocs/application_name/public';
    root $root_path;

    index index.php index.html index.htm;

    try_files $uri $uri/ @rewrite;

    location @rewrite {
        rewrite ^/(.*)$ /index.php?_url=/$1;
    }

    location ~ \.php {

        fastcgi_pass 127.0.0.1:9000;
        fastcgi_index /index.php;

        include /etc/nginx/fastcgi_params;

        fastcgi_split_path_info       ^(.+\.php)(/.+)$;
        fastcgi_param PATH_INFO       $fastcgi_path_info;
        fastcgi_param PATH_TRANSLATED $document_root$fastcgi_path_info;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
    }

    location ~* ^/(css|img|js|flv|swf|download)/(.+)$ {
        root $root_path;
    }

    location ~ /\.ht {
        deny all;
    }

} 

it works well, the only problem is that i need the root_path to be /srv/www/htdocs because I have other projects running there to. Whenever i change the line:

set $root_path '/srv/www/htdocs/application_name/public';

to:

set $root_path '/srv/www/htdocs';

the problem starts on url's like: localhost/application_name/public/users