Custom Atom elements without breaking compatibility?

[Nutter]

Is it possible to add custom metadata to an Atom feed, without breaking compatibility with feed readers?

I've added a custom namespace and custom elements to my feed, but Safari now refuses to read the feed, stating that “The feed could not be loaded because the content is not in a known feed format”.

I need this metadata in a custom application that loads the feed, but I want other feed readers to simply ignore these extra elements. Is that possible?

Excuse my ignorance, I'm a Cocoa developer and I know very little about this new-fangled interweb stuff...

<?xml version="1.0" encoding="utf-8"?>
<feed xmlns="http://www.w3.org/2005/Atom"
xmlns:b="http://www.example.com/">

  <title>Example</title>
  <link href="http://www.example.com/"/>
  <updated>2008-03-09T18:30:02Z</updated>
  <id>urn:uuid:60a76c80-d399-11d9-b93C-0003939e0af6</id>

  <entry>
    <title>Front door</title>
    <link rel="enclosure" type="video/quicktime" length="12345" href="http://www.example.com/"/>
    <id>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a</id>
    <updated>2008-03-09T18:30:02Z</updated>
    <b:cameraNum>0</b:cameraNum>
    <b:codec>MPG4</codec>
    <b:width>640</b:width>
    <b:height>480</b:height>
  </entry>
  
  <entry>
    <title>Street 1</title>
    <id>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6b</id>
    <updated>2008-03-08T20:31:56Z</updated>
    <b:cameraNum>1</b:cameraNum>
  </entry>

</feed>

 

[Nutter]

    <b:codec>MPG4</codec>

Ah, foolish me!

If I make sure that my tags match, then it works!