$postdata = 'vb_login_username=C!klodoL&vb_login_password=bN48 xc&cookieuser=1&s=&do=login&forceredirect=1&vb_log in_md5password=';
...
"Content-Length: ".length($postdata)."\r\n";
...
"Connection: close\r\n\r\n$postdata";