[Owncloud] ldap question

[Michael Pfitzner]

I need some help with the proper configuration of ldap.
The tree looks something like:
->dn
    ->ou=user
        ->uid=... all the information but no way to get all groups the
user is member of from here,
                        only users main group could be found

    ->ou=group
        ->cn=... here you can find the uid of all users who are member
of this group

my question is now, how do I restrict owncloud access to users of
certain groups, without changing anithing at the ldap tree.

I can filter for user whose maingroup is set in the user tree, but these
aren't all I want to give access to owncloud.

big thanx, michael