German:

Unter Windows 2003 mit SP1 ist es möglich, die Dateien und Ordner in den Freigaben auszublenden für die man keine Rechte hat. :-)

Dowload des Tools unter hier.

English:

"Windows Server 2003 Access-based Enumeration makes visible only those files or folders that the user has the rights to access. When Access-based Enumeration is enabled, Windows will not display files or folders that the user does not have the rights to access. This download provides a GUI and a CLI that enables this feature."

Dowload the tool here.

Quelle:
http://www.microsoft.com/downloads/details.aspx?FamilyId=04A563D9-78D9-4342-A485-B030AC442084&displaylang=en