public function addOAuth( $doc, $token) 
	{		
		$soapDoc = $doc;
		$envelope = $doc->documentElement;
		$soapNS = $envelope->namespaceURI;
		$soapPFX = $envelope->prefix;
		$SOAPXPath = new DOMXPath($doc);
		$SOAPXPath->registerNamespace('wssoap', $soapNS);
        $SOAPXPath->registerNamespace('wswsse', 'http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd');

		$headers = $SOAPXPath->query('//wssoap:Envelope/wssoap:Header');
		$header = $headers->item(0);
		if (! $header) {
			$header = $soapDoc->createElementNS($soapNS, $soapPFX.':Header');
			$envelope->insertBefore($header, $envelope->firstChild);
		}

		$authnode = $soapDoc->createElementNS('http://exacttarget.com', 'oAuth');
		$header->appendChild($authnode);
		
		$oauthtoken = $soapDoc->createElementNS(null,'oAuthToken',$token);
		$authnode->appendChild($oauthtoken);
	}