Disabling access for git to specific Directory with Apache Basic Authentication

["qvc99@xxxxxx" <qvc99@xxxxxx>]

I have git setup with my Apache2 server and it serves git request just fine. Now I want to setup Basic Authentication for this, so not everybody can use every directory. My goal is that only the ADMIN group has access to the complete `/var/www/html/git` directory and my GITGROUP can access *only* `/var/www/html/git/subdir` directories. However, while Apache is asking for credentials, with the setup (below) GITGROUP is still allowed to access *all* git directories. What am I doing wrong?

SetEnv GIT_PROJECT_ROOT /var/www/html/git
SetEnv GIT_HTTP_EXPORT_ALL
ScriptAlias /git/ /usr/lib/git-core/git-http-backend/
<Directory /usr/lib/git-core>
    Options +ExecCGI -MultiViews +SymLinksIfOwnerMatch
    AuthType Basic
    AuthName "Authentication Required"
    AuthUserFile "/etc/apache2/.htpasswd"
    AuthGroupFile "/etc/apache2/groups"
    Require group ADMIN GITGROUP

    Order allow,deny
    Allow from all
</Directory>
<Directory /var/www/html/git>
    AuthType Basic
    AuthName "Authentication Required"
    AuthUserFile "/etc/apache2/.htpasswd"
    AuthGroupFile "/etc/apache2/groups"
    Require group ADMIN
    Options -Indexes

    Order allow,deny
    Allow from all
</Directory>
<Directory /var/www/html/git/subdir>
    AuthType Basic
    AuthName "Authentication Required"
    AuthUserFile "/etc/apache2/.htpasswd"
    AuthGroupFile "/etc/apache2/groups"
    Require group ADMIN GITGROUP
    Options -Indexes

    Order allow,deny
    Allow from all
</Directory>