I know that this is an old thread but wanted to share that I had the same problem with the OP. matthuisman's suggestion didn't work on my setup on Ubuntu13.10 with apache2.4.6. Instead, I had to add the following to my /etc/apache2/sites-available/mysite.conf
<Directory /var/www/mysite/>
Options Indexes FollowSymLinks
AllowOverride All
</Directory>
Then reload apache with
sudo service apache2 restart
Hope this helps someone.