4.2: ACL problem: Copy of local ACL lost when removing all rights to a user

Found a strange behaviour when updating some ACL permissions on my 4.2 site.

My sub page inherit from several users and group from the home page. If I now update my left menu container and localy recopy the ACL (then Apply) and then remove all the rights to this local user, inheritance is activated again. If I directly recopy AND remove all permissions to the user and click on APPLY afterwards, it works.

So what is not working is if you make the process in two distinct steps: 1) you copy the ACL locally and 2) you remove all the rights to the user (= he can not access to the page any more)... Then clicking on ok, reactivate the inheritance -> so the user has still all the rights from the parten container... exactly the opposite of what you wanted to do.

The one step porcess works. And the problem seems to only occur by removing all permissions. It works fine if you only remove the Admin or Wrtie permission, but you let the read permisson.