Ordering of faceted navigation resultset through HippoFacetNavigationBean is wrong

I configured a facet node like described on http://www.onehippo.org/7_8/library/concepts/faceted-navigation/faceted-navigation-configuration.html, and specified an order as described in d) Sorting the documents in the resultset.
When I inspect the hippo:resultset node in the console, the ordering looks good.

But when I get the results from a HippoFacetNavigationBean (HippoFacetNavigationBean.getResultSet().getDocumentIterator() or HippoFacetNavigationBean.getChildBeans() ) the results are not ordered anymore.

I have tested this in Hippo 7.7.7 and in the latest release.