If you plan on leaving the *same instance* of Netscape (or any other
browser) running and allowing multiple users to access it, then I
don't think there's any hope of preventing people from seeing pages
requested by previous users of that browser instance. There is
nothing in HTTP that prevents browsers from keeping history lists of
previously visited documents, even if the documents are not supposed
to be cached or have expired from the cache.
--Shel Kaphan
sjk@amazon.com