DatePicker resetting to 1970

I've 1 date attribute and setting its values in two datePickers one for date another for time. Unfortunately the date keeps resetting to 1970. when I change the time datepicker. and to time 00:00 when I change the date value. Any ideas on how to get around this.
1 answers

Make a helper attribute for time, connect the time widget to that attribute and in the onchange add the timepart to the target date. That will combine date and time. Add that onchange also to the target date attribute date widget.