Code snippet from Sjeord Fischer on the OPML-DEV list:

var xslProcessor = new XSLTProcessor();
var outputDoc = document.implementation.createDocument("text/xml", "", null);
xslProcessor.transformDocument(xmlNode, xslNode, outputDoc, null);

(code taken from Q42's Mozilla2IE converter for Xopus, available at
xopus.org)
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