A while ago I spent a while configuring JRun to use the Xalan SAX parser, thinking incorrectly that CFMX could not do XML validation. My assumption for this was based on the CF documentation which points to DOM based parsing, as it turns out CFMX uses the Crimson as the underlying parser and by accessing the Java API it is totally possible to validate an XML document. Massimo of CFCDev list posted a few links to code snippets (validateXMLString [also available for download here] and validateXMLFile [also available for download here ]) that accessed aforementioned API and validated XML.