I've been trying to login to an https website without much luck. I started by using Firefox's HTTPfox plugin to capture all of the POST data that is sent when I login via the browser:

__EVENTTARGET    
__EVENTARGUMENT    
__VIEWSTATE       /wE<lots of random text>=
__EVENTVALIDATION  /wEWBwKC8PjxBAKA67T+BwKO6KL2BAKLq4PJCgL29+SDDQLV0uz
+nBgLC1O+bAovDyVQCQToaE9MTGjwpHkcZ9bRh
cid_654$tbSearch    
jsMenu    
cid_40$txtUsername  <username>
cid_40$txtPassword  <password>
cid_40$btnLogin     Login
[download]

I then created my perl code as follows:

#!/usr/bin/perl -w
use strict;
use WWW::Mechanize;

my $post_response = "";

my $m = WWW::Mechanize->new();
$m->agent_alias('Linux Mozilla');
$m->add_handler("request_send", sub { shift(@_)->dump(); return });

my $url = "http://alumni.nd.edu/s/1210/start.aspx?sid=1210&gid=1&pgid=
+3&cid=40";

$m->get($url);

$post_response = $m->submit_form(
    form_number => 1,
    button        =>    'cid_40$btnLogin',
    fields        => 
    {
        'cid_40$txtUsername'    =>     '<username>',
        'cid_40$txtPassword'    =>     '<password>',
        '__EVENTTARGET'            =>    '',
        '__EVENTARGUMENT'        =>    '',
        'cid_654$tbSearch'        =>    '',
        'jsMenu'                =>    '',
        'cid_40$btnLogin'        =>    'Login'
        
    }
    
    
);


printf("POST RESPONSE STATUS LINE: %s\n", $post_response->status_line)
+;
printf("POST RESPONSE HEADER TITLE: %s\n", $post_response->header('tit
+le'));
[download]

It's not logging me into the website. I can tell because the call to $post_response->header('title') at the bottom returns nothing, yet I know the page you go to after logging in has a title field. Here's an excerpt from my program's output following the POST command:

POST https://securelb.imodules.com/s/1210/index.aspx?sid=1210&gid=1&pg
+id=3&cid=40
Accept-Encoding: gzip
Referer: http://alumni.nd.edu/s/1210/start.aspx?sid=1210&gid=1&pgid=3&
+cid=40
User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.4) Gecko/2003
+0624
Content-Length: 9420
Content-Type: application/x-www-form-urlencoded

__VIEWSTATE=%2FwEPDwUKMjAwMzk3MTQyNA9kFgICAw8WAh4FY2xhc3MFDklNT0QzIGlu
+dGVyaW9yFgICAQ9kFhACAg8WAh4HVmlzaWJsZWcWBGYPDxYCHwFoZGQCAQ8PFgIfAWhkF
+gQCAg9kFgICAQ9kFgICAQ9kFgQCAQ9kFgJmDxQrAAIUKwACZBAWA2YCAQICFgMUKwACDx
+YGHgRUZXh0BQlEYXNoYm9hcmQeC05hdmlnYXRlVXJsBWdodHRwczovL2FkbWlubGIuaW1
+vZHVsZXMuY29tL2FkbWluL2luZGV4LmFzcHg%2Fc2lkPTEyMTAmZ2lkPTEmcGdpZD0yOT
+AmZG9jdHlwZT14aHRtbCZjaWQ9JmJwaWQ9MjkwJm11aWQ9HgVWYWx1ZQUJY2xpY2thYmx
+lFgIeBXN0eWxlBQ9jdXJzb3I6cG9pbnRlcjtkFCsAAg8WBh8CBQdDb250ZW50HwMFL2h0
+dHA6Ly9teW5vdHJlZGFtZS5uZC5l...
(+ 8908 more bytes not shown)
GET http://mynotredame.nd.edu/?sid=1210&gid=1&pgid=61&muid=AUTH_b97c52
+30-1f64-4005-abf8-3fd6c28b56a9
Accept-Encoding: gzip
Referer: http://alumni.nd.edu/s/1210/start.aspx?sid=1210&gid=1&pgid=3&
+cid=40
User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.4) Gecko/2003
+0624

(no content)
GET http://mynotredame.nd.edu/s/1210/start.aspx?sid=1210&gid=1&pgid=61
+&muid=AUTH_b97c5230-1f64-4005-abf8-3fd6c28b56a9
Accept-Encoding: gzip
Referer: http://alumni.nd.edu/s/1210/start.aspx?sid=1210&gid=1&pgid=3&
+cid=40
User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.4) Gecko/2003
+0624

(no content)
GET http://mynotredame.nd.edu/s/1210/start.aspx?sid=1210&gid=1&pgid=61
Accept-Encoding: gzip
Referer: http://alumni.nd.edu/s/1210/start.aspx?sid=1210&gid=1&pgid=3&
+cid=40
User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.4) Gecko/2003
+0624
Cookie: AL_LastUpdated=3/15/2013 9:54:25 AM; WOL_LastUpdated=3/15/2013
+ 9:54:25 AM; .ASPXIMODAUTH=D75599B33280C1BD9EA223B07B0AC3014377703CD7
+5F81AC75227DFFDB3745D1F0479573FFFD174B4A989B5A8492CAB1569C079B9E2F862
+AD1B9FCF61A5289FE15E1FE13169DFE6BCC55B82C396CF5360EDA625385BE95D46EF6
+CB853B08C222562E2C4D96CED1A63043E6A0A416B595C8505102DC48C3B5F21C039FA
+351EE0F88FD439C8AC41D58149CE174996C58CA50B2F4B5064EDC59DBAE7781EABC8E
+17D015B37862E22ABC7329171B6B2768FAB55DDD3657E33E3BA168BCE852D9056A160
+75F60
Cookie2: $Version="1"

(no content)
POST RESPONSE STATUS LINE: 200 OK
Missing argument in printf at www_debug.pl line 38.
POST RESPONSE HEADER TITLE:
[download]

Does anyone have any idea why it's not letting me log in? I tried including the __VIEWSTATE and __EVENTVALIDATION fields in my submission, but that didn't help anything.