Using PUT with PHP OAuth library

Question

I'm having a problem using the PUT HTTP method with the PHP OAuth library (http://www.php.net/manual/en/book.oauth.php)

What I need to do is pass some XML as the file to be PUT, but I am not sure how to send it with OAuth.

Here's what I have:

$xml = "<data><id>1234</id><something>i am now set to this</something></data>";

$oauth->fetch('api URL', array('body' => $xml), OAUTH_HTTP_METHOD_PUT, array("User-Agent" => "pecl/oauth"));

I get back a: [body_recv] => 401 - Unauthorized

I know I'm putting the content in the wrong place, but I can't find where it should go.

... Making GET requests for resources that require authorisation is fine.