Problems seeing attributes with SimpleXml

I'm running through the SimpleXml examples on  http://uk.php.net/simplexml.
Unfortunately I can't get Example 4 to work as advertised. When I do a
var_dump($xml) the $rating['type'] attributes do show up:

     ["rating"]=>
    array(2) {
      [0]=>
      string(1) "7"
      [1]=>
      string(1) "5"
    }

This is the pertinent bits of my configure: --with-libxml2 --with-dom
--with-simplexml --with-xsl

And phpinfo() shows:
  dom api version: 20031129
  libxml version: 2.6.2
  simplexml revision: $Revision: 1.132 $

Any ideas?

Philip