If you just want to retrieve a single file you don't need a robot.
It may be possible to somehow pass authorisation arguments to lynx -dump,
otherwise I recommend libwww-perl5 which comes with a program called
lwp-request which will allow this.
Check CPAN (via http://www.perl.com/) for the latest versions of
libwww-perl and the other bits and pieces it needs.
Hope this helps,
-- Martijn
Email: m.koster@webcrawler.com
WWW: http://info.webcrawler.com/mak/mak.html