JavaTest calls export() method of the interview during interview's saving to obtain environment. There is export() called for hidden questions not in path in this case. See stacktrace for example:
Exception in thread "AWT-EventQueue-0" java.lang.AssertionError
        at com.sun.tck.j2me.interview.CldcBaseCommInterview.exportCommunicationValues(CldcBaseCommInterview.java:470)
        at com.sun.tck.j2me.interview.CldcBaseCommInterview.access$500(CldcBaseCommInterview.java:63)
        at com.sun.tck.j2me.interview.CldcBaseCommInterview$3.export(CldcBaseCommInterview.java:141)
        at com.sun.tck.j2me.interview.lib.QuestionExtensionImpl.export(QuestionExtensionImpl.java:68)
        at com.sun.tck.j2me.interview.lib.NullQuestion.export(NullQuestion.java:71)
        at com.sun.interview.Interview.export0(Interview.java:1848)
        at com.sun.interview.Interview.export(Interview.java:1835)
        at com.sun.tck.j2me.interview.MidpTckBaseInterview.export(MidpTckBaseInterview.java:188)
        at com.sun.tck.j2me.interview.BasicTckInterview.getEnv(BasicTckInterview.java:225)
        at com.sun.javatest.InterviewParameters.getName(InterviewParameters.java:289)
        at com.sun.javatest.interview.BasicInterviewParameters.getName(BasicInterviewParameters.java:146)
        at com.sun.javatest.InterviewParameters.save(InterviewParameters.java:1569)
        at com.sun.tck.j2me.interview.MidpTckBaseInterview.save(MidpTckBaseInterview.java:355)
        at com.sun.javatest.InterviewParameters.saveAs(InterviewParameters.java:1507)
        at com.sun.javatest.InterviewParameters.save(InterviewParameters.java:1451)
        at com.sun.javatest.InterviewParameters.save(InterviewParameters.java:1435)
        at com.sun.javatest.exec.InterviewEditor.doSave(InterviewEditor.java:394)
        at com.sun.javatest.exec.InterviewEditor.save0(InterviewEditor.java:367)
        at com.sun.javatest.exec.InterviewEditor.save0(InterviewEditor.java:345)
        at com.sun.javatest.exec.InterviewEditor.perform(InterviewEditor.java:1132)
        at com.sun.javatest.exec.InterviewEditor$Listener.actionPerformed(InterviewEditor.java:1599)
        at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1995)
        at
....
 
CldcBaseCommInterview is interview which not in the path at all but export() is called for it's hidden question.