BuddyPress.org

I noticed in the showcase of other sites using buddypress that they have blogs made available for their users/members. I’ve been wanting to give that same opportunity for my buddypress powered social network. how do i enable my members to also have a blog of their own within my site. for now, I am the only one who can post a blog. the way i see possible for me to make a member able to post in the site’s blog is to change its role from subscriber to author. but i might not want to do that. all i want is to have them have their own blog as a member, but not as an author on my wp site. please help. thanks.