you mean that you are able to choose date as attribute value type in the attribute editor? Since the extension of RapidMiner to support date and time value types, I assume this change unintentionally affected the [tt]ExampleSource[/tt] operator or the attribute editor in particular. We will check that and post a reply with more information once we have done so.
it is actually desired that it is no longer possible to select "date" or "time" from the attribute editor or the ExampleSource wizard right now. You should choose "nominal" instead and apply the operator "Nominal2Date" which is able to transform the date to an actual date representation.