The Calendar and DateFormat of org.andromda.cartridges.jsf.converters.DateTimeConverter does not take into account the time zone that is used for the conversion to a date.
This means that a date that is entered in a non default locale timezone (and the default time zone for the jsf components is documented as UTC) will be redisplayed as a date in the locale default timezone -- it will redisplay as a different date than was entered.