<%
  ChartPostProcessor myChartPostProcessor =  new  ChartPostProcessor() {
       public   void  processChart(Object chart, Map params) {
        DecimalFormatSymbols formatSymbols =  new  DecimalFormatSymbols();
        formatSymbols.setDecimalSeparator('.');
        formatSymbols.setGroupingSeparator(' ');
        decimalFormat.setDecimalFormatSymbols(formatSymbols);

        CategoryPlot plot = ((JFreeChart) chart).getCategoryPlot();

        CategoryItemRenderer renderer = plot.getRenderer();
        renderer.setBaseItemLabelGenerator( new  StandardCategoryItemLabelGenerator("{2}", decimalFormat));
      }
    };
    pageContext.setAttribute("chartPostProcessor", myChartPostProcessor);
%>    
...
<cewolf:chartpostprocessor id="chartPostProcessor"/>