dynamic xi:include href attribute

Is there any way to set the href attribute on <xi:include> using a variable
in XSL? (XSLT-1.0/Xalan-2.7.0)

Example:
<xsl:variable name="path" select="concat($current.doc.path,'CVS\Entries')"/>
<xi:include parse="text" href="{$path}"/>

I get an error from the processor because it's using the literal '{$path}'.
Does Xalan just not support dynamic href attributes? Or is this not even
possible?

I'm open to suggestions get this behaviour working...

Cheers,

WS