Automatically publish posts from XML file (NOT RSS/Atom)

I am receiving content published via an XML file that is formatted as follows:

<newsfeed>
?
<article id="102023368">
<title>Headline of newest story</title>
?
<content>
The content of the story is written here
</content>
<keywords>keyword 1</keywords>
<date>1225981694</date>
</article>
?
<article id="102023375">
<title>Headline of an earlier story</title>
?
<content>
The content of the story is written here
</content>
<keywords>keyword 2</keywords>
<date>1225981679</date>
</article>

How can I automatically create and publish posts from this file on my blog?

I tried to use the WP-o-Matic plugin for this, but it didn’t recognise the XML file when I added a link to it.

PS. I realise some people use these methods to scrape other people’s content. I intend to use this for entirely legitimate purposes.