stylesheet requres attribute: version

[Charles Yates]

Hello list,
     I get a javax.xml.tranform.TranformerConfigurationException
when creating a new Transformer instance with a stylesheet that
is a javax.xml.source.DOMSource object.  The stylesheet works
fine as a StreamSouce, and when using saxon, a DOMSource.  Is
this a bug or am I doing something wrong?  I attach a short java
class that exhibits this behavior.  I'm using xalan 2.2-D10.  Stack
trace is rather long so I won't include it here this time.
thanks, Charles
import javax.xml.parsers.*;
import javax.xml.transform.*;
import javax.xml.transform.stream.*;
import javax.xml.transform.dom.DOMSource;
import java.io.StringReader;
import org.xml.sax.InputSource;
public class XalanBug {

  private static final String stylesheet =
    "<?xml version=\"1.0\"?>\n"+
    "<xsl:stylesheet version=\"1.0\""+
    "                xmlns:xsl=\"http://www.w3.org/1999/XSL/Transform\";>"+
    "  <xsl:template match=\"/\">"+
    "    <xsl:copy-of select=\".\"/>"+
    "  </xsl:template>"+
    "</xsl:stylesheet>";

  private static final String document =
    "<?xml version=\"1.0\"?>\n"+
    "<root>booga</root>";

  public static void main(String[] args) {

    try {

      DocumentBuilderFactory dfact =
        DocumentBuilderFactory.newInstance();

      DocumentBuilder builder =
        dfact.newDocumentBuilder();

      DOMSource domStylesheet =
        new DOMSource(builder.parse(new InputSource(new 
StringReader(stylesheet))),"");

      StreamSource streamStylesheet =
        new StreamSource(new StringReader(stylesheet),"");  //saxon doesn't 
like null systemId

      TransformerFactory tfact =
        TransformerFactory.newInstance();

      Transformer streamTrans =
        tfact.newTransformer(streamStylesheet); //this works fine

      streamTrans.transform(new StreamSource(new StringReader(document)),new 
StreamResult(System.out));
      
      Transformer domTrans =
        tfact.newTransformer(domStylesheet);     //Exeption thrown here

      domTrans.transform(new StreamSource(new StringReader(document)),new 
StreamResult(System.out));

    }
    catch (Exception e) {
      e.printStackTrace();
    }
  }
}