XSL fragment within Javascript not-well formed!!!!!

Here is my trouble...
I would like to dynamically generate the test condition for a 'when'
element using javascript.
But, I can't even get the code below to work because the
"MSXML2.FreeThreadedDOMDocument.3.0" parser expects the closing 'when'
tag before the closing script tag.

<script type="text/javascript">
  <![CDATA[document.write(']]><xsl:choose><xsl:when
test="FName='Steve'"><![CDATA[');]]>
</script>

I would like to reference form elements in the test condition to make
the condition dynamic if possible.

Thanks,
~Steve