I'm not really sure what "Compartment Authorization" means, but you can do some very sophisticated and (from what I can tell) pretty secure with an extensive set of Access Control abilities for Enterprise Collaboration by using Namespaces (for a "compartment"?) with MediaWiki using a combination of:
http://www.mediawiki.org/wiki/Extension:Lockdown - Page lockdowns http://www.mediawiki.org/wiki/Extension:NSFileRepo - Restricts Access to Images, files, etc.
We make use of Page Security [0] to handle this issue. I'm honestly not sure how secure it is since I've never checked, but it is good enough to keep the lay user from seeing things, which is really all we needed in our case.
I ported it to 1.18.1 when we began to use it. There is a link to the port on the talk page.
This approach has a weakness because there is no explicit inheritance. A user adding a new page or file needs to explicitly specify the NameSpace in order for that information to be restricted.
For us what they have to do is add the page to a certain category, for example if the page is to only be viewable by the HR department, they might add [[Category:HR]] to the page. So while the inheritance issue is still a problem at the very least it organizes the content as well.
Hopefully this helps someone, Derric Atzrott Computer Specialist Alizee Pathology