code: public void startPrefixMapping(String prefix, String uri)
            throws org.xml.sax.SAXException
    {
  
      // m_nsSupport.pushContext();
      // this.getNamespaceSupport().declarePrefix(prefix, uri);
      //m_prefixMappings.add(prefix); // JDK 1.2+ only -sc
      //m_prefixMappings.add(uri); // JDK 1.2+ only -sc
      m_prefixMappings.addElement(prefix); // JDK 1.1.x compat -sc
      m_prefixMappings.addElement(uri); // JDK 1.1.x compat -sc
    }
docs: Receive notification of the start of a Namespace mapping.
  
  <p>By default, do nothing.  Application writers may override this
  method in a subclass to take specific actions at the start of
  each element (such as allocating a new tree node or writing
  output to a file).</p>
  
  @param prefix The Namespace prefix being declared.
  @param uri The Namespace URI mapped to the prefix.
  @see org.xml.sax.ContentHandler#startPrefixMapping
  
  @throws org.xml.sax.SAXException Any SAX exception, possibly
  wrapping another exception.