John:

Sorry, I couldn't let it pass, it is not often that you can make a wrong century joke.

Now back to your questions.  I am not familiar with Joomla but am a little familiar with DNN.

I think that DNN will definitely satisfy your requirement to group users by logical groups, in DNN lingo, Roles.  DNN has a pretty robust user roles and groups infrastructure that the modules can take advantage of.  This architecture is also flexible and expandable at the admin level without having to modify the underlying code.

Regarding the document management functionality, I think that you will need a third party module for that (or develop your own in any .Net language).  You can look at what is available in the commercial DNN market place in the following links: http://marketplace.dotnetnuke.com/ and http://www.snowcovered.com.

Hope this helps, I also hope that you give DNN a chance.

And welcome back to the future... (sorry again)

Carlos

That's twice a yes. And ... webDAV access of these documents, also per user permissions, content search, categorization etc etc ... And all of this on WISDOM (Windows IIS, SQL, DotNetNuke, and Modules)

Peter