I use the jQuery UI datepicker to let the user select a date. It has some shortcuts so that it can be controlled using the keyboard:
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This is not configurable through datepicker. You would have to change the _doKeyDown
method source here.
The easiest way to do this would be to extend the widget. It would look something like this:
$.extend($.datepicker, {
_doKeyDown: function(event){
//copy original source here with different
//values and conditions in the switch statement
}
});