header.setStartDate(ganttChart.getCalculatedStartDate());
//
// Add a default calendar called "Standard"
//
final ProjectCalendar calendar = file.addDefaultBaseCalendar();
calendar.setWorkingDay(Day.SATURDAY, false);
calendar.setWorkingDay(Day.SUNDAY, false);
final DayHolder dh = new DayHolder(ganttChart.getCalculatedStartDate());
for (int i = 0; i < 3000; i++) { // Endless loop protection (paranoia)
dh.add(Calendar.DAY_OF_MONTH, 1);