When I edit a user, User Options > Roster, and add a new roster item, I can choose to add the user to a group, freehand. When I type in a name of a existing group or a non-existing group, the user is still not added to any groups. The roster page shows none.
I also noticed there is no option to change the “Subscription” option without rediting the user in the roster. Would be nice to have this as an option at creation time.