$result = $client->customerCustomerCreate($session, array(
        'email' => $email,
        'firstname' => $firstname,
        'lastname' => $lastname,
        'password' => $password,
        'website_id' => 1,
        'store_id' => 1,
        'group_id' => 1,
        'external_user_id' => $eternal_id,
        'confirmation => 1
    ));
    var_dump($result);