curl vbulletin login and post data

i have a code login vbb by curl
function vBulletinLogin($user, $pass)
{
$md5Pass = md5($pass);
$data = "do=login&url=%2Findex.php&vb_login_md5password=$md5Pass&vb_login_username=$user&cookieuser=1";
$ch = curl_init();
$reffer = 'http://aaa.com/f42/lalala_lblblb-91451.html';
curl_setopt ($ch, CURLOPT_URL, "http://aaa.com/login.php?do=login"); // replace ** with tt
curl_setopt ($ch, CURLOPT_USERAGENT, "Mozilla/4.0 (compatible; MSIE 5.01; Windows NT 5.0)");
curl_setopt ($ch, CURLOPT_TIMEOUT, '10');
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch,CURLOPT_POSTFIELDS,$data);
curl_setopt($ch, CURLOPT_COOKIEJAR, "d:/tmp/codecall_$user.txt");
curl_setopt($ch, CURLOPT_COOKIEFILE, "d:/tmp/codecall_$user.txt");
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, 1);
curl_setopt ($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_REFERER, $reffer);
$store = curl_exec ($ch);
print $store;

}
vBulletinLogin("aaaa","123456");


i want after login then post comment is' abc................' at link 'http://aaa.com/f42/lalala_lblblb-91451.html'

please help me support this

thanks