Hi dsr,
try to use this code
Appointment appt = new Appointment();
DateTimeFormat calformat = DateTimeFormat.getFormat("yyyy-MM-dd hh:mm:ss");
appt.setStart(calformat.parse("2012-06-29 04:04:05"));
appt.setEnd(calformat.parse("2012-06-29 04:05:30"));
appt.setTitle("CCM20125000001");
appt.setStyle(AppointmentStyle.GREEN);
appt.setDescription("Billing");
But make sure the date and time of start and end..
i mean edit it by your day and time