Jython Interpreter breaks at automatic loading of imports

java.lang.NoClassDefFoundError: fiji/InspectJar
	at common.AbstractInterpreter.getDefaultImports(AbstractInterpreter.java:981)
	at common.AbstractInterpreter.getImportStatement(AbstractInterpreter.java:947)
	at common.AbstractInterpreter.importAll(AbstractInterpreter.java:960)
	at Jython.Jython_Interpreter.run(Jython_Interpreter.java:73)
	at ij.IJ.runUserPlugIn(IJ.java:235)
	at ij.IJ.runPlugIn(IJ.java:198)
	at ij.Executer.runCommand(Executer.java:150)
	at ij.Executer.run(Executer.java:68)
	at java.lang.Thread.run(Thread.java:748)