samba - Apr 2013 - hide unwriteable files and windows xp

I need to hide the listing of files to multiple users, but only allow access to
the file if you know the exact path and filename of the file in the form of
\\server\share\filename.txt.  I am using the hide unwriteable files = yes flag
to accomplish this and it works as expected with windows 7.  However, windows XP
gives the error that windows cannot find the file.  Is there a different
setting, or perhaps a different way to accomplish the same results, that works
with windows xp?