Hi Clarence;
Yes, PowerServer Mobile at this time does not support the calendar DDDW edit mask feature. You can use ZhoKai's excellent suggestion as one workaround. However, if you have 100's of DWO's that is a lot of column editing work. Also, if your App is used in the Web or native Windows O/S - the spin look & feel may not be the best UI for thos date columns ( DDDW Calendar works OK in PowerServer Web).
Another alternative is to do a RYO (roll-your-own) version of the Calendar. You can see this approach in the PFC and also STD Frameworks. This allows you to have one DWO that works across all App environments that implements a consistent interface.
Here is the STD example:
Mobile:
The above Look & Feel is the same in Native and Web as well ....
Web:
Native:
Food for thought
HTH
Regards ... Chris