Something like this should work:

use LWP::UserAgent;

my $ua = LWP::UserAgent->new;
$ua->agent("google.com");
my $response = $ua->get('http://dragcave.ath.cx/viewdragon/Vjwf', Refe
+rer => 'http://www.google.com');
print $response->content;
[download]

However, I really doubt thats the kind of security they'd be using. Usually, the referring URL would be a URL on their own site. If they discriminate at all, it'll be purely on user-agent string.

-David