I've tried to submit the form using the submit method, but it seems the first form on the page (a website search box) is submitted instead of the login form.

use strict;
use WWW::Mechanize;
use WWW::Mechanize::FormFiller;
use URI::URL;

my $agent = WWW::Mechanize->new( autocheck => 1 );
my $formfiller = WWW::Mechanize::FormFiller->new();
$agent->env_proxy();

  $agent->follow('http://use.perl.org/');
  $agent->get('http://use.perl.org/');
    $agent->form(1) if $agent->forms and scalar @{$agent->forms};
  $agent->form_number(2);
  { local $^W; $agent->current_form->value('query', 'WWW::Mechanize');
+ };
  $agent->submit();
__END__
C:\>perl -MWWW::Mechanize -e"die WWW::Mechanize->VERSION"
1.11_01 at -e line 1.

C:\>perl -MWWW::Mechanize::Shell -e shell
Module File::Modified not found. Automatic reloading disabled.
SetConsoleMode failed, LastError=|6| at C:/Perl/site/lib/Term/ReadKey.
+pm line 268.
>open http://use.perl.org/
Use of uninitialized value in concatenation (.) or string at C:/Perl/s
+ite/lib/WWW/Mechanize.pm line 1743, <IN> line 1.
Can't find any link matching http://use.perl.org/ on this page () at C
+:/Perl/site/lib/WWW/Mechanize/Shell.pm line 1028
Can't call method "code" on an undefined value at C:/Perl/site/lib/WWW
+/Mechanize/Shell.pm line 1034, <IN> line 1.
>get http://use.perl.org/
Retrieving http://use.perl.org/(200)
http://use.perl.org/>
http://use.perl.org/>
http://use.perl.org/>forms
Form [1]
GET http://use.perl.org/search.pl
  query=                         (text)
  <NONAME>= Go                   (submit)
Form [2]
GET http://search.cpan.org/search
  mode=module                    (option)   [*module/Module|dist/Distr
+ibution|author/Author|doc/Documentation]
  query=                         (text)
  <NONAME>=Search                (submit)
Form [3]
POST http://use.perl.org/login.pl
  unickname=                     (text)
  returnto=//use.perl.org/       (hidden readonly)
  op=userlogin                   (hidden readonly)
  upasswd=                       (password)
  login_temp=<UNDEF>             (checkbox) [*<UNDEF>/off|yes/Public T
+erminal]
  userlogin=Log in               (submit)
http://use.perl.org/>form 2
GET http://search.cpan.org/search
  mode=module                    (option)   [*module/Module|dist/Distr
+ibution|author/Author|doc/Documentation]
  query=                         (text)
  <NONAME>=Search                (submit)
http://use.perl.org/>value query WWW::Mechanize
http://use.perl.org/>submit
200
http://search.cpan.org/search?mode=module&query=WWW%3A%3AMechanize>
http://search.cpan.org/search?mode=module&query=WWW%3A%3AMechanize>
http://search.cpan.org/search?mode=module&query=WWW%3A%3AMechanize>scr
+ipt foo.pl
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