symfony2 rewrite rules .htaccess app.php

I uploaded my symfony2 project to server grove. The main page loads, but all the links are broken. I tried adding app.php to the web address. It did work, but:

I have routes like this one:

www.something.com/app.php/something

I want them to be:

www.something.com/something.

I've been reading, and I should put some rewrite rules on the .htaccess.

I found these rules, but they don't seem to work:

<IfModule mod_rewrite.c>
    RewriteEngine On
    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteRule ^(.*)$ app.php [QSA,L]
</IfModule>

Try this in your .htaccess file (inside the web directory):

<IfModule mod_rewrite.c>
    Options +FollowSymlinks
    RewriteEngine On

    # Explicitly disable rewriting for front controllers
    RewriteRule ^app_dev.php - [L]
    RewriteRule ^app.php - [L]

    RewriteCond %{REQUEST_FILENAME} !-f

    # Change below before deploying to production
    #RewriteRule ^(.*)$ /app.php [QSA,L]
    RewriteRule ^(.*)$ /app_dev.php [QSA,L]
</IfModule>

To improve upon whistlergreg's answer, I added a line so that the bundles folder is not broken. This will make sure external resources such as images are not broken.

<IfModule mod_rewrite.c>
    Options +FollowSymlinks
    RewriteEngine On

    # Explicitly disable rewriting for front controllers
    RewriteRule ^/web/app_dev.php - [L]
    RewriteRule ^/web/app.php - [L]

    # Fix the bundles folder
    RewriteRule ^bundles/(.*)$ /web/bundles/$1  [QSA,L]

    RewriteCond %{REQUEST_FILENAME} !-f
    # Change below before deploying to production
    #RewriteRule ^(.*)$ /web/app.php [QSA,L]
    RewriteRule ^(.*)$ /web/app_dev.php [QSA,L]
</IfModule>

You don't have enabled rewrite module. This code is executed if mod_rewrite.c is enabled. You must only enable mod_rewrite in apache2. http://www.unixmen.com/how-to-enable-and-disable-apache-modules/

For example in Ubuntu:

sudo a2enmod rewrite
sudo service apache2 restart