Commented Unassigned: Up/Down on Keyboard not working for DataTimePicker [20963]

I've seen [this resolved bug](http://wpftoolkit.codeplex.com/workitem/20269), but I have the exact issue in my computer.

Mouse wheel (when mouse is over the DataTimePicker control) does work.
but keyboard Up/Down buttons do nothing.

I've tried to specify _CultureInfo="en-GB"_ but it changed nothing.

VS2012, Win8, Version 2.1.0.0
Comments: ** Comment from web user: itsho **

Hi.

I've tried to re-create the issue on a new project and I didn't managed to do that.
so I guess it's related to my project and the complexity of joining WinForms + overriding ProcessCmdKey + showing WPF window by using Show() instead of ShowDialog().

since my project is now getting rid of WinForms form, I guess that it won't happen again...

thank you!