I've tested the modification by Fabio Bot with the auto completion of the year in IB_Date component and it works good.
Just some general consideration:
a) since this will have no sense if AutoFill is true, and since they have the same goal (ease user input reducing keystrokes), there should be a single property to regulate both, like:
AutoCompletion (acNone, acFill, acYearComplete)
b) would be good if it will work with a two year definition too, so I could enter 05/04 and have 05/04/02.
c) you can't write such input facility with every possible combination of date format in mind, but I think that the most common are mm/dd/yy, dd/mm/yy and yy/mm/dd (or with yyyy). It would be great if the control could fill the most part of information it can, like if I enter "05" consider this always a day specification, and so add month and year, whatever format I'm using (so acYearComplete will be acComplete).
d) additional UnboundDisplayFormat and UnboundEditMask property (maybe a shorter name, but with the same prefix) to exploit the full possibilities of the control in unbound mode too.

The a) idea will broke backward compatibility a little, but it will make the control more usable and will save future headaches.
Fabio, IBO community and Jason input is required ;)
Regards
Marco Menardi