title: Ant check if a directory (and sub directories) contains a certain file
body: <p>I'm trying to check in Ant if a directory (and sub directories) contains a certain file</p>
  
  <p>I'm using ant contrib with :</p>
  
  <pre><code>&lt;if&gt;
    &lt;available&gt;
      &lt;filepath&gt;
        &lt;fileset dir="myDir"&gt;
          &lt;include name="**/*.AEF" /&gt;
        &lt;/fileset&gt;
      &lt;/filepath&gt;
    &lt;/available&gt;
  &lt;then&gt;
    &lt;fail/&gt;
  &lt;/then&gt;
  &lt;/if&gt;
  </code></pre>
  
  <p>I want to fail if there is at least a file ending with "AEF" in myDir or one of its sub-directories.
  But this fails even if no "*.AEF" file is found</p>