[xslt] libxslt fails, xsltproc works

["Sam Liddicott" <sam liddicott com>]

I've got an xslt file (with associated xslt library) that works with
xsltproc but when run via libxslt fails with:

compilation error: file /root/deb/citadel/webcit/str%3Atokenalize.xslt
line 14 element param
element param only allowed within a template, variable or param
compilation error: file /root/deb/citadel/webcit/str%3Atokenalize.xslt
line 15 element param
element param only allowed within a template, variable or param
..

The offending text is:
13: <func:function name="str:tokenalize">
14:   <xsl:param name="string" select="''" />
15:   <xsl:param name="delimiters" select="' &#x9;&#xA;'" />


The same file as at the top:
                xmlns:func="http://exslt.org/functions";
as does the including xslt file, which includes with:

  <xsl:include href="/root/deb/citadel/webcit/str:tokenalize.xslt"/>

So why doesn't it like me when running via libxslt?

It clearly finds the file, the working xsltproc invocation (on the same
system with the same xslt files) is:
xsltproc static/clean_html.xslt t

Sam