docs: private boolean scanSurrogates(XMLStringBuffer buf)
          throws IOException, JspCoreException {
  
          int high = scanChar();
          int low = peekChar();
          if (!XMLChar.isLowSurrogate(low)) {
          	throw new JspCoreException("jsp.error.xml.invalidCharInContent", new Object[] { Integer.toString(high, 16) });
              //err.jspError("jsp.error.xml.invalidCharInContent", Integer.toString(high, 16));
              //return false;
          }
          scanChar();
  
          // convert surrogates to supplemental character
          int c = XMLChar.supplemental((char)high, (char)low);
  
          // supplemental character must be a valid XML character
          if (!XMLChar.isValid(c)) {
          	throw new JspCoreException("jsp.error.xml.invalidCharInContent", new Object[] { Integer.toString(c, 16) });
              //err.jspError("jsp.error.xml.invalidCharInContent", Integer.toString(c, 16)); 
              //return false;
          }
  
          // fill in the buffer
          buf.append((char)high);
          buf.append((char)low);
  
          return true;
  
      }