Now allows the user specify the map and/or reduce output key/value classes via custom user defined properties (pentaho.map.output.key.class.override, pentaho.map.output.value.class.override, pentaho.reduce.output.key.class.override and pentaho.reduce.output.value.class.override). Setting one or more of these overrides the automatic setting of output classes to match Kettle types coming out of mapper/reducer transformations.