XSLT rendering to HTML in IE7 performance

I'm not sure if this is the correct forum for this question, but I have an XML file with the following reference to an XSLT file that transforms it to HTML when it is loaded in a browser. 

<?xml-stylesheet type="text/xsl" href="xml2html.xslt"?>

It renders correctly, but it takes an awfully long time.  For comparison, I loaded the same file in both IE7 and in Firefox 2.0.  In Firefox it renders in 2 seconds; in IE7 it takes 15 seconds to render. 

Any ideas would be greatly appreciated!