Illegal-Date-Value
This property allows you to define a date that will be returned to the program when the user inputs an illegal date. The program can check against this date in order to intercept an illegal input and manage it.
The date format used by this property must match the date format specified by Value-Format.
When this property is not set, the Date-Entry control returns the last valid date to the program when the user inputs an illegal date. If there’s no valid date in the history, then the current date is returned.
 
Example - Define a date-entry control that returns the 1th January 9999 when an illegal date is inputted by the user
screen section.
...
  03 screen-1-de-1 Date-Entry
     line 21.2
     column 49.5
     size 14.5 cells 
     lines 3.1 cells 
     id 17
     layout-data 17
     century-date
     value-format davf-yyyymmdd
     illegal-date-value 99990101
     .