use WWW::Mechanize;

my $username = 'user';
my $password = 'pass';
my $url      = 'http://www.xyz.com/Login.aspx';
my $mech     = WWW::Mechanize->new(autocheck => 1);

$mech->get( $url );
$mech->form_name("login form name");
$mech->field("username", $username);
$mech->field("password", $password);
$mech->click("login button/submit name");

$mech->content() =~ /sm.th. from Track.aspx/ and print "logged in\n"

__END__

##</code><code>##

mech-dump "http://some.web-site.com/login.html"