title: Java 5 Does not validate DTD
body: <p>I am working with a vendor applet, The applet works fine with JRE 1.4.2_X and 1.6.X but fails on every version of 1.5.X. Running with 1.6 is not an option due to another application conflict that does not play nice with Java 6.</p>
  
  <p>The issue I believe is that the DTD is not being validated. This is causing the "not declared" problem and the resulting nullpointer.</p>
  
  <pre><code> Error: Fri Aug 28 11:21:29 EDT 2009 org.xml.sax.SAXParseException: 
   Element type "UserSessionList" is not declared.
   java.lang.NullPointerException
  </code></pre>
  
  <p>I tried changing the default validation class but the problem remains unchanged.</p>
  
  <pre><code> -Djavax.xml.validation.SchemaFactory:http://relaxng.org/ns/structure
   /1.0=org.apache.xerces.jaxp.validation.XMLSchemaFactory
  </code></pre>
  
  <p>Is there another validation I can use for this? </p>
  
  <p>I don't really have the option of modifying the code the applet is beyond end of life from the vendor so getting support from them is unlikely. So any workarounds cannot involve changing code since we do not own it.</p>