non null foreign keys

But I'll explain my problem.  In the database I have a table let's say invoice and invoicedetail

InvoiceDetail has a foreign key to Invoice called InvoiceID.  Since I don't want any orphan InvoiceDetail the InvoiceID field is not nullable in the database.

Devforce is creating the the key as an int and adds 

[IbVal.RequiredValueVerifier( ErrorMessageResourceName="InvoiceDetail_InvoiceID")]

 [IbEm.ForeignKey("Invoice")]

 

The problem I get is that since the field is an int the default value is 0.  Then when I go to validate the entity it passes without any validation errors.  I'm assuming this is because the RequiredValueVerifier is only looking for a null.  Is there a way that I can tell devforce to treat the 0 as if it were a null?  I could write my own verifier and then set up a metadata class to do my own validation but then I would have to do that for every foreign key in my database.  

Hue

I'm adding a feature request to see if we can have this "RequiredEntityVerifier" to be a part DevForce validation.