Thanx a lot buddy, your code has worked for me.
Here is the code:
$soap_do = curl_init();
curl_setopt($soap_do, CURLOPT_URL, $url );
curl_setopt($soap_do, CURLOPT_CONNECTTIMEOUT, 10);
curl_setopt($soap_do, CURLOPT_TIMEOUT, 10);
curl_setopt($soap_do, CURLOPT_RETURNTRANSFER, true );
curl_setopt($soap_do, CURLOPT_SSL_VERIFYPEER, false);
curl_setopt($soap_do, CURLOPT_SSL_VERIFYHOST, false);
curl_setopt($soap_do, CURLOPT_POST, true );
curl_setopt($soap_do, CURLOPT_POSTFIELDS, $post_string);
curl_setopt($soap_do, CURLOPT_HTTPHEADER, array('Content-Type: text/xml; charset=utf-8', 'Content-Length: '.strlen($post_string) ));
curl_setopt($soap_do, CURLOPT_USERPWD, $user . ":" . $password);
$result = curl_exec($soap_do);
$err = curl_error($soap_do);