You can send Post data through the curl library in PHP:
For example, this will log into BG:
PHP Code:
$cookiefile = tempnam("/tmp", "cookies");
$login_post_url='http://www.bluegartr.com/forum/login.php?do=login';
$agent="Mozilla/4.0 (compatible; MSIE 5.01; Windows NT 5.0)";
$reffer='http://www.bluegartr.com/forum/forumdisplay.php?f=68';
$loginpost="vb_login_username=##USERNAME##&cookieuser=1&vb_login_password=##PASSWORD##&s=&do=login&vb_login_md5password=&vb_login_md5password_utf=";
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL,$login_post_url);
curl_setopt($ch, CURLOPT_USERAGENT, $agent);
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_POSTFIELDS,$loginpost);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, 1);
curl_setopt($ch, CURLOPT_REFERER, $reffer);
curl_setopt($ch, CURLOPT_COOKIEFILE, $cookiefile);
curl_setopt($ch, CURLOPT_COOKIEJAR, $cookiefile);
$result = curl_exec ($ch);
curl_close ($ch);
Dunno how much this will help you, but someone mentioned sending post data, this is how you do it.