@Override
 public Boolean getObject() {
   McSubTaskDefAnswerDefinitionsItem answerDef = nestedModel.getObject();
   NamedString ns = answerDef.getItemCorrect();
   if (ns != null) return Boolean.TRUE;
   else return Boolean.FALSE;
 }
 /*
  * (non-Javadoc)
  *
  * @see org.apache.wicket.model.Model#setObject(java.io.Serializable)
  */
 @Override
 public void setObject(Boolean iscorrect) {
   McSubTaskDefAnswerDefinitionsItem answerDef = nestedModel.getObject();
   if (iscorrect) {
     answerDef.setItemCorrect(answerDef.getItemIncorrect());
     answerDef.setItemIncorrect(null);
   } else {
     answerDef.setItemIncorrect(answerDef.getItemCorrect());
     answerDef.setItemCorrect(null);
   }
 }