Cannot cleanup container which contains license objects


I am cleaning up a container (OU) which is not used any more.

But I cannot delete it because it contains Novell netware license objects.

Novell\ nLSProduct\=BorderManager Access Control\ nLSVersion\=370x

When I try to delete it via iManager.
(Error -629) The object being deleted or modified is not a leaf object. A container object that does not contain any objects is considered a leaf object, and therefore can be deleted.

I have no netware server(s) anymore in my tree so I can't delete it via NLM tools.