DateTimePicker - Eingegebene Zeit wird nicht übernommen?

[Bummi]

Delphi-Quellcode:

var
 t:TTime;
begin
  DateTimePicker1.DateTime := IncSecond(DateTimePicker1.DateTime, -1);
  Showmessage(DateTimeToStr(DateTimePicker1.Time) +'-'+ FloatToStr(DateTimePicker1.Time));
  t := Frac(DateTimePicker1.Time);
  Showmessage(DateTimeToStr(t) +'-'+ FloatToStr(t));
end;