Just a quick note so that it gets into the Google help engine. By default the copy of Ant that is included with Eclipse does not reference it’s own internal copy of JUnit on it’s class path, to change this open up the preferences window (hit command-comma if you’re on a Mac) and open the Ant/Runtime node then add the JUnit location to the global path. If you’re doing full-source editing (which is highly recommended for all Eclipse users!) then you can just add a workspace reference and it will work fine.