I responded to this yesterday, but I don't see either your question or the answer on the archive (which is odd, because the archive contains other questions posted today that I haven't seen yet in the email).
Here's the answer again:
Thanks for reporting this, but I will need a complete executable stylesheet and source document before I can determine whether the error is in your code or in mine.
Michael Kay

From: saxon-help-admin@lists.sourceforge.net [mailto:saxon-help-admin@lists.sourceforge.net] On Behalf Of Jose Antonio Illescas del Olmo
Sent: 13 April 2005 09:21
To: saxon-help@lists.sourceforge.net
Subject: [saxon] possible bug with variable scope

Hello Michael,

I have an global-parameter called "mode" with an empty value in runtime

    <xsl:param name="mode"/>

after I use a template-parameter with same name ("mode")

    <xsl:apply-templates select="*[1]" mode="template.list.view.criteria">
        <xsl:with-param name="mode" select="'list.without.selection'"/>

 but template-parameter is empty into template "template.list.view.criteria" when exist a static value ('list.without.selection')

This never occurs with saxon-8.1.  (is an error?)

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