Different rights on different subtrees for same user group

Hello to all!

We have a group of editors that has to edit in “live mode” a subtree in our site and has to edit in “draft mode only” another subtree of the same site.

Is it possible? All my tests suggest that rights are additive… Our 2 subtrees have different user groups with appropriate rights and our editor group inherit both groups.

How can we manage that kind of configuration?

A million thanks!

Eric T.