Alterar a data do sistema

Procedure TForm1.Button1Click(Sender: TObject);
begin
SetNewTime(1998,2,10,18,07);
end;

function SetNewTime(Ano, Mes, Dia, hour, minutes: word): Boolean;
var
st:TSYSTEMTIME;
begin
GetLocalTime(st);
st.wYear := Ano;
st.wMonth := Mes;
st.wDay := Dia;
st.wHour := hour;
st.wMinute := minutes;
if not SetLocalTime(st) then
Result := False
else
Result := True;
end;