Matthias - You didn't give us a sample of your command invocation.
           In the past, some users have been confused as to the order
of coding operands on the command line.  Make sure you have something
like:  'dsmc s -subdir=yes /FilesysName' .
If you still find no directories being backed up, you should assure
that you are at the latest software levels, and thereafter report
to IBM Support as a problem.  (Remember that Selective does not back
up empty directories.)
    Richard Sims, Boston University OIT