If you define a filed from type "date", you cant assigne a value "null", therefore all date fields will get a value DD MM YYYY.
If you use DB for a to list, you may have:
Started at, To do until, Finished at.
maybe you know not all of the vlues, you should leave them empty.
BUT
If you save this, ALL 3 field will have date values in it!
thanks for your help
regards Peter