add this section to existing configuration
  <section id="imagej" name="Image Processing">
    <tool file="data_source/upload.xml" />
    <tool file="imagej/extractChannelAs32bit.xml" />
    <tool file="imagej/ijFilters.xml" />   
    <tool file="imagej/pixelMath.xml" />   
    <tool file="imagej/calculatorMacro.xml" />   
    <tool file="imagej/applyMacro.xml" />
  </section>