having header bottom line with header.rule

[Marie Sauvage - EBM WebSourcing <marie.sauvage@ebmwebsourcing.com>]

Hi all !

I'm new in docbook and try to customize my pdf output, generated with fop.
I succeeded in customizing some things for footers and headers like content depending on type of pages (titlepage, book page, set page, etc.) or layout with footer.table.Now I have problems with the header : when I set header.rule to 1, nothing happens, I can't see the bottom line.

I have set this at the bottom of my stylesheet, with others parameters :
  <!-- activating headers & footers rules -->
  <xsl:param name="header.rule" select="1"></xsl:param>
  <xsl:param name="footer.rule" select="1"></xsl:param>

It works well with footer.rule : line appears and disappears when I set 1 or 0, I also can change it by changing border width in foot.sep.rule.
But with header, I can't manage to do anything : header.rule has no effect, nor head.sep.rule which I copied from nwalsh/pagesetup.xsl to my custom fo.xsl. I've also tried to remove the test <xsl:if test="$header.rule != 0"> to force the line on headers, but still no change on headers...

I haven't touched the header.table and head.sep.rule but even when I copy them in my file, nothing change...

Has anyone an idea of what I am doing wrong ? (or what I am not doing...)

thank you very much in advance.
Marie.