UnsupportedRepositoryOperationException in RulesListener

The following scenario results in an javax.jcr.UnsupportedRepositoryOperationException in the RulesListener:

1) Create a new page in the navigation menu container (I've used Web Templates-based prepackaged demo) with the option "Don't create Jahia page "
2) An entry is created in the nav menu with the "No title"
3) Update it and provide title
4) When clicking on the "OK" in the update container engine there is an exception in the server console (see attached stacktrace.txt).