Sample code for updating Rackspace Cloud DNS

dnsupdate.php

<?php
require '/path/to/rackspace.php';
$DOMAIN_EMAIL = 'something@example.com';
// establish our credentials
$cloud = new OpenCloud\Rackspace(RACKSPACE_US,
  array('username' => $USERNAME, 'apiKey' => $APIKEY ));
// connect to the DNS service
$dns = $cloud->DNS();
// get a list of domains
$dlist = $dns->DomainList();
while($domain = $dlist->Next()) {
	$domain->Update(array('emailAddress'=>$DOMAIN_EMAIL));
}