I just tried it and it works : inserted a date in the add item window, opened a grid, put duedate as the source. Item appeared.

 

Check out your other filters.

- Alphanumeric filter bar

- Date filter bar.

- common filter in the source bar

 

Disable all of these and see.

 

(Pierre : the way the Alphanumeric filter bar and Date filter bar interact with the normal filter -- the one in the source bar -- is not easy to grasp... There's a hierarchy between filters which demands a fairely high level of abstract thinking, especially when what you're focussing on is not about understanding filters but just getting things done. Maybe the applied filters should be "graphed out"  in a window... so that  the user can see which filter does what and in what order... It's not easy to get and it's easy to loose plenty of time trying to filter effectively. For instance, using the date filter is so challenging to me -- and I consider myself a fairely advanced user --, especially when other filters are "on", that I almost never use it. This filtering stuff is, IMO, high priority since it's used all the time. Named filter would help, of course...)