post_install() {
  if [ ! -f etc/xml/catalog ]; then
    usr/bin/xmlcatalog --noout --create etc/xml/catalog
  fi
  _NEW=`echo $1 | sed 's|\(.*\)\-.*|\1|'`

  usr/bin/xmlcatalog --noout --add "rewriteSystem" \
    "http://docbook.sourceforge.net/release/xsl-ns/${_NEW}" \
    "/usr/share/xml/docbook-xsl-ns/${_NEW}" \
    etc/xml/catalog

  usr/bin/xmlcatalog --noout --add "rewriteURI" \
    "http://docbook.sourceforge.net/release/xsl-ns/${_NEW}" \
    "/usr/share/xml/docbook-xsl-ns/${_NEW}" \
    etc/xml/catalog &&

  usr/bin/xmlcatalog --noout --add "rewriteSystem" \
    "http://docbook.sourceforge.net/release/xsl-ns/current" \
    "/usr/share/xml/docbook-xsl-ns/${_NEW}" \
    etc/xml/catalog &&

  usr/bin/xmlcatalog --noout --add "rewriteURI" \
    "http://docbook.sourceforge.net/release/xsl-ns/current" \
    "/usr/share/xml/docbook-xsl-ns/${_NEW}" \
    etc/xml/catalog
}

post_upgrade() {
  post_remove $2
  post_install $1
}

post_remove() {
  _OLD=`echo $1 | sed 's|\(.*\)\-.*|\1|'`
  usr/bin/xmlcatalog --noout --del "/usr/share/xml/docbook-xsl-ns/${_OLD}" etc/xml/catalog
}
