security between captive portal logged in computers.?

From:	Manickam Murugan <Admin at easybrowsing dot com>
To:	m0n0 <m0n0wall at lists dot m0n0 dot ch>
Subject:	security between captive portal logged in computers.?
Date:	Fri, 11 Feb 2005 16:13:28 +0530

Dear Sir

We have a m0n0wall network.
Two computers are logged-in through captive portal.
Is there any way to block windows-filesharing between two logged-in
computers.?

Thanks in advance.
Murugan