[xsl] Replace function with <> characters?

[Rune Stilling <subs@xxxxxxxxxx>]

Hi I'm trying to do a simple replace of the following form:

<xsl:variable name="markup_topic_text" select="replace 
($markup_topic_text, '<', 'xxx')"/>
<xsl:variable name="markup_topic_text" select="replace 
($markup_topic_text, '>', 'yyy')"/>

I was told at the Saxon mail list that this is not possible and that  
I should use '&lt;' like:

<xsl:variable name="markup_topic_text" select="replace 
($markup_topic_text, '&lt;', 'xxx')"/>
<xsl:variable name="markup_topic_text" select="replace 
($markup_topic_text, '&gt;', 'yyy')"/>

But this only replaces "&lt;"/"&gt;" and not "native" '<' characters.

What to do?

Thanks
Rune