Mozilla and the document() function

Does Mozilla 1.x's implementation of the XSLT document() function work
with URLs?

I have been able to read in local files, e.g.:

  <xsl:variable name="data" select="document('test.xml'))"/>

but if I try to read the same file through a web server it isn't 
able to read it:

  <xsl:variable name="data"
select="document('http://localhost/test.xml'))"/>

The Content-Type of the response from the web server is "text/xml".

This works fine with Xalan and MSXML for example.

Is there something I'm missing? Any insight on using document() to
access XML documents over URLs would be appreciated.

Thanks.

 XSL-List info and archive:  http://www.mulberrytech.com/xsl/xsl-list