my $ua = LWP::UserAgent->new;
$ua->agent("MyApp/0.1 ");

$url = 'http://localhost/web_authenticate_post.cgi';

$req = HTTP::Request->new(POST => $url);
$req->content_type('application/x-www-form-urlencoded');

$req->content('username=security&password=security&login=Login');

my $res=$ua->request($req);

if($res->is_success){
   $res1 = $ua->request(HTTP::Request->new(GET=>'http://localhost/config.cgi'
));
   print $res1->content;
}
else{
   print $res->status_line;
}