$params = '&action=user_create';
$params .= '&account_id='.$account_id;
$params .= '&gateway_pass='.$gateway_pass;
$params .= '&user='.$member_user;
$params .= '&pass='.$member_pass;

// optional data
$params .= '&first_name=john';
$params .= '&last_name=doe';
$params .= '&address1=1234 Hudson Lane';
$params .= '&address2=Suite 11';
$params .= '&city=San Diego';
$params .= '&state=Ca';
$params .= '&zip=92345';
$params .= '&country=USA';
$params .= '&email=johndoe@hotmail.com';

$result = sendPost($gateway_ip,$params,true);//use ssl