Comment 2 for bug 700107

Workaround:

As you said you need to load the module:
# cat /etc/apache2/mods-available/auth_openid.load
LoadModule authopenid_module /usr/lib/apache2/modules/mod_auth_openid.so

Enable it:
# cd /etc/apache2/mods-enabled
# ln -s ../mods-available/auth_openid.load .

Use this in your Apache Directive:
AuthOpenIDEnabled On
AuthType OpenID

Restart Apache:
# apache2ctl restart

Now you should see the OpenID login screen on your webpage.

In PHP the user name is here:
echo $_SERVER['REMOTE_USER'];

If you want to give access to special users as you are used to do with "require user alice bob" do this:
http://findingscience.com/mod_auth_openid/authuserprogram.html