Don't remember seeing this in any of the beta builds (at least up until 6).
Try this:
In the backend have the User Profile set to allow access to Everybody, and also have Connections enabled and public.
Then click on a user's profile. You'll be able to view it. Then go to their Connections tab, and try clicking on the profile of one of their connections.
You'll get a message saying you need to be logged in to view.
This shouldn't be the case, as you should be able to see the connection's profile page.