#55 NullPointerException

[Vendy]

java version "1.5.0_09"
Java(TM) 2 Runtime Environment, Standard Edition

$jpf +search.class=.search.RandomSearch +jpf.listener=gov.nasa.jpf.tools.StateSpaceDot build/examples/HelloWorld
Path Limit = 0
JavaPathfinder v4.1 - (C) 1999-2007 RIACS/NASA Ames Research Center

====================================================== system under test
application: build/examples/HelloWorld.class

====================================================== search started: 8.2.08 14:27
Hello World!
paths = 1
java.lang.NullPointerException
at gov.nasa.jpf.tools.StateSpaceDot.addNode(StateSpaceDot.java:342)
at gov.nasa.jpf.tools.StateSpaceDot.endGraph(StateSpaceDot.java:198)
at gov.nasa.jpf.tools.StateSpaceDot.searchFinished(StateSpaceDot.java:108)
at gov.nasa.jpf.search.SearchListenerMulticaster.searchFinished(SearchListenerMulticaster.java:148)
at gov.nasa.jpf.search.Search.notifySearchFinished(Search.java:352)
at gov.nasa.jpf.search.RandomSearch.search(RandomSearch.java:84)
at gov.nasa.jpf.JPF.run(JPF.java:392)
at gov.nasa.jpf.JPF.main(JPF.java:319)