Tracking the status of messages using the Esendex PHP SDK - Full details here: http://developers.esendex.com/

TrackMessageStatus.php

$authentication = new \Esendex\Authentication\LoginAuthentication(
    "EX000000", // Your Esendex account reference
    "[email protected]", // Your login email
    "password" // Your password
);
$headerService = new \Esendex\MessageHeaderService($authentication);
$message = $headerService->message("messageId");
print_r($message->status());