Hey Davide D'Alto, regarding using StringDateTypeDescriptor, I also think it can be used but I'm wondering whether we rather should only persist the date or time part, respectively. At least for...

@Temporal(DATE) java.util.Date date;
@Temporal(TIME) java.util.Date time;

... I think that's what a user would expect. Basically the same for @Temporal(DATE) java.util.Calendar date; but we'd have to store the TZ info there in addition. WDYT?