The concept is similar to the self-service combo (where you put "..." in the setdef parameter and it returns exitcode 29 when you attempt to display the drop-down), except here you activate it by adding type ||v to the date type codes. Presumably this might be useful in cases where you like the look of the edit portion of the date picker, but want to display a more specialized calendar when the user clicks the drop-down button.
See Date Picker Control (INFLD) in AUIxs for related information.
