code: public void testSerializableTaskVariable(){
    Task task=taskService.newTask();
    task.setName("MyTask");
    taskService.saveTask(task);
    Map<String,Object> vars=new HashMap<String,Object>();
    MyVariable myVariable=new MyVariable("Hello world");
    vars.put("theVar",myVariable);
    taskService.setVariables(task.getId(),vars);
    MyVariable variable=(MyVariable)taskService.getVariable(task.getId(),"theVar");
    assertEquals("Hello world",variable.getValue());
    taskService.deleteTask(task.getId(),true);
  }
  