Regression: A document being edited can be requested to be (un)published by another user

In CMS 7.8 when a document is edited by another user, no publish or unpublish actions are allowed.
Now however, both scheduled and non-scheduled actions are enabled through the menu and the scheduled actions actually can be performed.
The non-scheduled actions (publish/unpublish) can be invoked but result in an error dialog being shown ("Exception: an error occurred").