If you havce stored procedures and packages that use a string entry to get a date and do not want to or can not take the time to change the date, you can convert windows dates to Y2K strings using the following Delphi function:
strDate := formatDateTime( 'dd"/"mm"/"yyyy', DatePicker.Date);
The choice of the formatting string - 'dd"/"mm"/"yyyy' is up to you, but be sure it matches your expectations in Oracle.