arshal(HierarchicalStreamReader reader,
                        UnmarshallingContext context) {
                Birthday birthday = new Birthday();
                if (reader.getAttribute("gender").charAt(0) == 'm') {
                        birthday.setGenderMale();
                } else {
                        birthday.setGenderFemale();
                }
                reader.moveDown();
                Person person = (Person)context.convertAnother(birthday, Person.class);
                birthday.s