gentoo-overlay/media-sound/protux/metadata.xml

<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE pkgmetadata SYSTEM "http://www.gentoo.org/dtd/metadata.dtd">
<pkgmetadata>
  <herd>proaudio</herd>
  <herd>java</herd>
  <upstream>
    <remote-id type="sourceforge">protux</remote-id>
  </upstream>
</pkgmetadata>