gentoo-overlay/app-emacs/emacs-common-gentoo/metadata.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE pkgmetadata SYSTEM "http://www.gentoo.org/dtd/metadata.dtd">
<pkgmetadata>
<herd>emacs</herd>
<use>
  <flag name='emacs22icons'>Install Emacs 22 style icons</flag>
  <flag name='games'>Support shared score files for games</flag>
</use>
</pkgmetadata>