Request for subtitle of unexpected element: slides

[Mathieu Malaterre <mathieu.malaterre@gmail.com>]

Dear all,

  I am getting this funny warning message:

Request for subtitle of unexpected element: slides

  When generating a docbook-slides (3.4.0 release). It seems to be
coming from the following:

<xsl:template match="*" mode="subtitle.markup">
  <xsl:message>
    <xsl:text>Request for subtitle of unexpected element: </xsl:text>
    <xsl:value-of select="local-name(.)"/>
  </xsl:message>
  <xsl:text>???SUBTITLE???</xsl:text>
</xsl:template>

  However I do not understand what I need to change in my docbook
slides to get rid of this warning.

Thanks !
-- 
Mathieu