GitLab 8 gitlab-git-http-server with Apache/Passenger

After upgrading from GitLab 7.14 to 8.0 we are having problems with the new gitlab-git-http-server. I’ve found some configuration instructions (found in the GitLab recipes repo: https://gitlab.com/gitlab-org/gitlab-recipes/tree/master/web-server/apache) for using GitLab with Apache and Unicorn, but no instructions for using Apache with Passenger. I still do not know how I have to configure Apache with all these different proxy settings. Cloning a repo by using SSH works still properly, but using HTTPS not.

Content of /etc/apache2/sites-enabled/default-ssl:

<IfModule mod_ssl.c>
<VirtualHost _default_:443>
...
include /etc/apache2/includes.d/gitlab.conf

SSLEngine on
...
</VirtualHost>
</IfModule>

Content of /etc/apache2/includes.d/gitlab.conf:

Alias /gitlabtest "/var/www/gitlab"
<Directory /var/www/gitlab>
    Options -MultiViews
    SetEnv RAILS_RELATIVE_URL_ROOT "/gitlabtest"
    PassengerAppRoot "/home/git/gitlab"
</Directory>

As you can see we are using relative url for accessing GitLab over https://our_hostname_fqdn/gitlabtest. Instructions found in GitLab recipes repo say that with Apache we have to start gitlab-git-http-server by listening on a TCP port instead of using a unix socket.

Content of /etc/init.d/gitlab:

...
gitlab_git_http_server_options="-listenUmask 0 -listenNetwork tcp -listenAddr localhost:8181 -authBackend http://127.0.0.1:8080"
...

How should the Apache configuration with options like Rewrite, ProxyPassReverse and so on should look like? How do I have to start the gitlab-git-http-server with which options? TCP port or sockets?

I would really appreciate if someone can help me. Thanks in advance!