API keys appear to be totally broken

Hi,

Following on from this issue:
http://drupal.org/node/305011#comment-1019188

I've tried really hard to reverse engineer the API keys for Services module, cos the documentation seems to be waaay out of date, and it just is not working.

It seems to me API keys are not working at all right now. They don't even seem to be used by node.get and views.get methods at all. I have generated an API key using the Services Keys admin page (at admin/build/services/keys).

My PHP (or what matters, at any rate) looks like this:

session_start();

function getUniqueCode($length = "") {
  $code = md5(uniqid(rand(), true));
  if ($length != "") return substr($code, 0, $length);
  else return $code;
}

$timestamp = (string) strtotime("now");
$domain = 'defaqto.com';

//this is the array key, generated for domain 'localhost'
$kid = '34f37fc6819763d326b55e55b330138f';
$nonce = getUniqueCode("10");
$method_name = 'file.getNodeFiles';

$hash_parameters = array(
  $timestamp,
  $domain,
  $nonce,
  $method_name,
);

$hash = hash_hmac("sha256", implode(';', $hash_parameters), $kid);

$request = xmlrpc_encode_request(
  $method_name, array(
    $hash,
	$domain,
	$timestamp,
	$nonce,
	session_id(),
	19,
  )
);

$context = stream_context_create(
  array(
    'http' => array(
    'method' => "POST",
    'header' => "Content-Type: text/xml",
    'content' => $request
    )
  )
);

print '<h1>Sent</h1><pre>'. htmlspecialchars(print_r($request, true)) .'</pre>';

$file = file_get_contents("http://cms.defaqto.com/services/xmlrpc", false, $context);

$response = xmlrpc_decode($file);
if (xmlrpc_is_fault($response)) {
    trigger_error("xmlrpc: $response[faultString] ($response[faultCode])");
} else {
    print '<h1>Received</h1><pre>'. htmlspecialchars(print_r($response, true)) .'</pre>';
}

If I do this in the Service Browser I always get "Invalid API key" and if I do it in my test script I get absolutely nothing. =(

I really need to get this resolved. Can anyone help me? Without API keys the Services module is useless and I can't work out if it's something I'm doing or the module is broken. If I can't get it working soon I'll be forced to revert to a previous version that worked.