Possible Bug with IOS7/ DateElement

I have just upgraded to the alpha channel so that I can test my App (Uses Monotouch.Dialog) against IOS7. App seems to run fine and picks up the IOS 7 styling ok - but I have one issue with the DateElement

I create the DateElement at Class Level :

internal DateElement DateEntry = new DateElement("hi", DateTime.Now);

and then I add it to the root element

root.Add (new Section(text[SelectedCreditDebit]) {DateEntry});

When I run the App, the dialog View Controller loads fine and the date is displayed - however when I click on the date to edit it - a black screen is displayed - no date picker.

Is this a bug in the Monotouch.Dialog Library??

Thanks Ash...