/**
     * test PROPFIND on calendar
     * 
     * @group ServerTests
     */
    public function testPropfindThundebird()
    {
        $credentials = $this->getTestCredentials();
        $account = $this->getAccountByName($credentials['username']);
        $this->assertInstanceOf('Tinebase_Model_FullUser', $account);
        $containerId = $this->getPersonalContainer($account, 'Calendar_Model_Event')->getFirstRecord()->getId();
        $request = \Zend\Http\PhpEnvironment\Request::fromString(<<<EOS
PROPFIND /calendars/{$account->contact_id}/{$containerId}/ HTTP/1.1
Host: localhost
Depth: 1
Content-Type: application/xml; charset="utf-8"
User-Agent: Mozilla/5.0 (X11; Linux i686; rv:15.0) Gecko/20120824 Thunderbird/15.0 Lightning/1.7

<?xml version="1.0" encoding="UTF-8"?>
<D:propfind xmlns:D="DAV:" xmlns:CS="http://calendarserver.org/ns/" xmlns:C="urn:ietf:params:xml:ns:caldav"><D:prop><D:resourcetype/><D:owner/><D:current-user-principal/><D:supported-report-set/><C:supported-calendar-component-set/><CS:getctag/></D:prop></D:propfind>
EOS
);
        $_SERVER['REQUEST_METHOD'] = $request->getMethod();
        $_SERVER['REQUEST_URI'] = $request->getUri()->getPath();
        $_SERVER['HTTP_DEPTH'] = '0';
        $request->getServer()->set('PHP_AUTH_USER', $credentials['username']);
        $request->getServer()->set('PHP_AUTH_PW', $credentials['password']);
        $request->getServer()->set('REMOTE_ADDR', 'localhost');
        ob_start();
        $server = new Tinebase_Server_WebDAV();
        $server->handle($request);
        $result = ob_get_contents();
        ob_end_clean();
        $responseDoc = new DOMDocument();
        $responseDoc->loadXML($result);
        #$responseDoc->formatOutput = true; error_log($responseDoc->saveXML());
        $xpath = new DomXPath($responseDoc);
        $xpath->registerNamespace('cal', 'urn:ietf:params:xml:ns:caldav');
        $xpath->registerNamespace('cs', 'http://calendarserver.org/ns/');
        $nodes = $xpath->query('//d:multistatus/d:response/d:propstat/d:prop/d:current-user-principal');
        $this->assertEquals(1, $nodes->length, $responseDoc->saveXML());
    }