rights modification and indexing service

Hi

We have problems with the indexing service and the rights managment :

When we're adding a new user in the rights tab on a "folderish" document :
    - the indexing service update the current document and it becomes 
visible for the new user autorised,
    - but the documents with the facet "folderish" contained into it 
doesn't been re-indexed... so their aren't visible in the content tab.

O.