DOCBOOK-APPS: XSL: Docbook to foreign DTD

I'm converting Docbook into a given DTD and have problems mapping
xref.  It looks pretty easy:
Docbook: <xref linkend="something"/> is going to be 
<xref xlink:href="something"/> in the foreign DTD. 

My template

<xsl:template match="xref">
  <xref>
    <xsl:attribute name="xlink:href"><xsl:value-of select="@linkend"/></xsl:attribute>
  </xref>
</xsl:template>

generates <xref href="something"/>, so I assume that gives me problems
with some sort of namespace.  So my question is, how do I generate an
attribute name with a colon?  I don't think I'll have luck in changing
the foreign DTD...

Jochen

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