LWP and java servlet error (newbie)

I'm trying to hit this URL (corporate intranet):

https://www.dmotorworks.com/ia.ui/broker/login

.... using the following code:

use LWP;
my $URL = "https://www.dmotorworks.com/ia.ui/broker/login";
my $browser = LWP::UserAgent->new( );
my $response = $browser->get($URL);
print $response->content;

When I go to that URL using Firefox or IE, I get a login screen. When
I try it using LWP, I get a 'servlet exception error'.

I nstalled Crypt::SSLeay (WinXP SP2) via the instructions here:
http://johnbokma.com/perl/https.html

I'm able to reach https sites (such as https://www.paypal.com), but
not the one I mentioned above.

If it's possible to get in there using LWP, I may post again
requesting help trying to log in to this site :) I used to access the
site via LWP by manually generating cookie file from Firefox and using
HTTP::Cookies::Netscape. I can still do that, but they updated the
site last weekend so that the cookie expires every 24 hours when it
used to expire every 30 days.
Before they did the update, I could reach the login screen, but could
never get the authentication to work. But now that I'm having to
generate a new cookie every day to make my scripts work, I really need
to get this working :)