SimpleXML not loading all fields

For some reason my SimpleXML implementation is not grabbing all the data:

$feed = simplexml_load_file('http开发者_Python百科://www.example.com/feed');
print_r($feed);

#This leaves out <media:thumbnail> and <dc:creator>

What's going on?

Thanks for your help.

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You need to use the children method, specifying the namespace. The default access and iteration methods only operate on the default namespace.

See here for an example.

EDIT: Broken link above, see here for the last version available from Wayback.