LinkageError with 2.2.1 - really simple project

[ry...@kodak.com]

Hello,
  I just downloaded Xerces 2.2.1 from the website and attempted to build a 
very very simple project but when I go to run it, I get the following 
error:
 java.lang.LinkageError: loader constraints violated when linking 
org/w3c/dom/Document class

 The only two jars in my classpath are:
 xmlParserAPIs.jar
 and 
 xercesImpl.jar

 I am using the 1.3.1_05 JDK.
 
Code:

 import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.FactoryConfigurationError;
import javax.xml.parsers.ParserConfigurationException;
import java.io.File;
import java.io.IOException;
...
        try {
            DocumentBuilderFactory dbf = 
DocumentBuilderFactory.newInstance();
            dbf.setNamespaceAware(true);
            DocumentBuilder db = dbf.newDocumentBuilder();
            Document doc = db.parse(new File(m_filename));
            System.out.println ( "First node: " + 
doc.getFirstChild().getNodeName() );
        } catch (FactoryConfigurationError error) {
            error.printStackTrace();
        } catch (ParserConfigurationException e) {
            e.printStackTrace();
        } catch (SAXException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

Any suggestions on why I am getting this linkage error? I am at a complete 
loss at how to fix this.
-Ryan