I'm trying to set add Active directory groups, to various different groups on an Ubuntu (11.10) box.
I've managed to get it to accept Active Directory users, but when I try adding AD Groups to etc\groups\ there is no joy..
Groups in *nix (that includes Ubuntu) cannot contain other groups.
AD groups are available as regular groups if you have AD membership configured correctly, try
and see if the groups are listed, if yes, then you can use them directly:
chgrp ad-group-A /some/dir
You should take a look at PowerBroker Identity Services (formerly Likewise Open). There's an Open edition and an Enterprise edition, they allow much more fine-grained mapping of AD groups then is possible just using Winbind for AD membership. The Enterprise edition gives you complete control over group policy. But the Open edition covers 99% of the cases I require on a day to day basis. I highly recommend looking at the documentation for PowerBroker to see if it will be a good fit for your use case.