Possible causes for "schema feature not recognized for SAX driver"

I am trying to execute a program developed elsewhere, and I see the following exception:

org.jdom.RuntimeExc开发者_C百科eption: http://apache.org/xml/features/validation/schema 
feature not recognized for SAX driver org.apache.cimson.parser.XMLReaderImpl

This program ran successfully a few months ago, but my development platform was rebuilt (apparently into a different configuration). Any ideas why this program is now throwing the above exception?

This is an Xerces feature (as listed here). Thus, you need to download and put Xerces in the classpath.