I've always been able to use sites that require logins on Safari v4 in Tiger...it just doesn't show the history. I've also seen newer machines (Safari v5 I believe) do the same. To be frank, wouldn't a big reason for using private browsing in the first place be to surf these sites (i.e. social networking, online dating, etc) without leaving a history. If you can't get onto those types of sites in PB, what's the point? Thanks.