how to allow certain IPs to access my directory

[Takeo Kameda]

Hi All.  This is my first post.
I would like to allow only certain IPs to access some of my site.  I know
that
can be done in orion-web.xml using "access-mask/ip-access", but I believe
it can only be applied to the whole application.  What I want to do is to
block
IPs only to a certain directory.  Is there any easy way to do that, like
using
.htaccess for apache?  or, do I have to write my own servlet filter for
that?
thanks in advance.