[oXygen-user] DTD validation and namespace prefixes

Hello, I have a Schematron schema that formerly was validating successfully against a DTD, but now with Oxygen 8.2, is failing validation. The Schematron schema begins <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE sch:schema SYSTEM "schematron.dtd"> <sch:schema xmlns:sch="http://www.ascc.net/xml/schematron" defaultPhase="done"> The DTD, schematron.dtd, begins <!ELEMENT schema ( title?, ns*, phase*, p*, pattern+ , p*, diagnostics )> As you can see, the DTD does not allow for the sch: namespace prefix on the <schema> element. Yet the validation used to be successful. Was the old behavior incorrect? Maybe I should just stop using schematron.dtd and use the Schematron-validator that Oxygen provides? Lars