XmlRPC and newMediaObject

Hi,
i am playing around with the MetaWeblog-API and wondering why my files (when i am calling newMediaObject and sending all data who is required by the API-Doc – https://www.xmlrpc.com/metaWeblogApi) are only ascii.

This is a problem with the line 835:
$success = fwrite($ifp, $bits);
The API-Doc said i must encode the data with base64, but in this line there is no decode.

I’ll fixed the problem with:
$success = fwrite($ifp, base64_decode($bits));

But is this a real bug or is there something i don’t understand?

Thanks
Kelloggz