Mapping a specific LDAP Group to confluence-user group during login

[hutzlerhe]

Hi experts,

currently we evaluate Crowd.  We want only users for a certain LDAP group to
be allowed to use confluence by assigning confluence-users group during login.

Lets says LDAP has following groups: GroupA (UserA) , GroupB (UserB) and GroupC (UserC).
We only want that UserA, which is member of GroupA, can login to Confluence.

• To achieve this we have created a LDAP Delegation Directory and configured the confluence  App via: Application -> Directories & Groups using the following Options
• Who can authenthicate : GroupA
• Automatically assigned to : confluence-users

Login for UserA works fine ( member of GroupA) but the confluence-users group is not
automatically assigned to UserA after login.

Note: If we assign the confluence-users group via Default group memberships in our
RZ Delagtion Directory UserA can access the Confluence App, but this is not what
we want.

Sould this work ? If yes what is wrong in my setup ?