Multisite logins

Hi, I was wondering if this is either a bug or part of the features. You see, I installed the release candidate 3.0 to give a go at the multisite feature and got that working fine. However, when using plugins to activate privacy, such at Private WordPress and wp-private, I’m not the getting the expected results:

Created:

blog1.domain.com
blog2.domain.com

Then created users for each individualy:

blogger1 for blog1.domain.com
blogger2 for blog2.domain.com

So far, so good. When I activate the privacy plugin and try to access the blog without logging in, I’m redirected to the login screen. However, when logged as blogger1, I get the see the content of blog1.domaine.com.

My problem is if I then surf over to blog2.domain.com while logged in as blogger1, I can access it anyway!

Any thoughts on this?
much appreciated!
-steph