[xep-support] table header orphaned

[relliquest at planet.nl]

Dear All,
I have this problem that table header are being orphaned, left alone on the previous page. Also on the next page, the table header is not the top item.  
I have read the xep conformance stating that all cells must have keep-together.within.column="always", but that does not seem to help at all.
Any clues why this is the case.  Below I have a very small fo, which creates really bad PDF. I am using xep354.

<?xml version="1.0"?>
<fo:root xmlns:fo="http://www.w3.org/1999/XSL/Format">
 <fo:layout-master-set>
  <fo:simple-page-master master-name="page" page-height="6.4cm">
   <fo:region-body region-name="xsl-region-body" margin="0.7in"/>
  </fo:simple-page-master>
 </fo:layout-master-set>

 <fo:page-sequence master-reference="page">
  <fo:flow flow-name="xsl-region-body">
   <fo:table space-before="1.8cm" space-before.conditionality="retain">
    <fo:table-column column-number="1"/>
    <fo:table-header>
     <fo:table-row>
      <fo:table-cell keep-together.within-column="always" border="1pt solid">
       <fo:block font-weight="bold">Header Row</fo:block>
      </fo:table-cell>
     </fo:table-row>
    </fo:table-header>
    <fo:table-body>
     <fo:table-row>
      <fo:table-cell keep-together.within-column="always" border="1pt solid">
       <fo:block>Body Row 1</fo:block>
      </fo:table-cell>
     </fo:table-row>
     <fo:table-row>
      <fo:table-cell keep-together.within-column="always" border="1pt solid">
       <fo:block>Body Row 2</fo:block>
      </fo:table-cell>
     </fo:table-row>
    </fo:table-body>
   </fo:table>
  </fo:flow>
 </fo:page-sequence>
</fo:root>