xsl/xhtml: passing through comments

I want to pass through comments from DocBook/XML to XHTML:
------------------------------------------------------------------
<arg><option><link linkend="opt-libdir">-B &lld;</link></option></arg>
<!-- #ifdef UNIX -->
<arg><option><link linkend="opt-link-set">-K
   <replaceable>linking-set</replaceable></link></option></arg>
<!-- #endif -->
------------------------------------------------------------------
===>
------------------------------------------------------------------
[<code class="option"><a href="#opt-libdir">-B <em class="replaceable"><code>lisp-lib-dir</code></em></a></code>]
<!--#ifdef UNIX-->
[<code class="option"><a href="#opt-link-set">-K
   <em class="replaceable"><code>linking-set</code></em></a></code>]
<!--#endif-->
------------------------------------------------------------------

I have this:

------------------------------------------------------------------
<xsl:template match="comment()">  <!-- pass through comments -->
 <xsl:text>&#10;</xsl:text>
 <xsl:comment><xsl:value-of select="normalize-space(.)"/></xsl:comment>
 <xsl:if test="not(following-sibling::comment())">
  <xsl:text>&#10;</xsl:text></xsl:if>
</xsl:template>
------------------------------------------------------------------

for some reason, the last "xsl:if" does not work: I do not get the
newline after <!--#ifdef UNIX-->, I get a space instead:

------------------------------------------------------------------
<!--#ifdef UNIX--> [<code class="option"><a href="#opt-link-set">-K
   <em class="replaceable"><code>linking-set</code></em></a></code>]
------------------------------------------------------------------

why?

-- 
Sam Steingold (http://www.podval.org/~sds) running w2k
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