If it's just a single page that you need to get through https and you have lynx available, I usually tend to take the easy way out:

open IN,"/usr/local/bin/lynx -auth=$name:$password -source https://sec
+ure.website.com?foo=bar |" ) or die "Could not open pipe: $!\n";
local $/;
my $html = <IN>;
close IN;
[download]

At least you don't have to load a lot of modules for something that only needs to be done now and then.

Not sure this will help you in this particular case. But lynx can handle cookies alright, so maybe it's just a matter of setting up the right cookie jar.

Liz