SubSonic ActiveRecord templates: generated code produces error converting int? to int

I just started exploring SubSonic 3's ActiveRecord, and it's initial code generation has created errors.

    Cannot implicitly convert type 'int?' to 'int'. 
    An 开发者_JAVA技巧explicit conversion exists (are you missing a cast?)

Here's the line it throws the exception on:

    public override int GetHashCode() {
        return this.pkEmp;
    }

The exception is understandable since the column pkEmp is defined as int? _pkEmp;. Any ideas on why the two are out of sync?

There can be no null value in the column defined as primary key. If so, make sure you have a problem with join (if the entity comes from a "View").

As John Sheehan pointed out, it's important to make sure that any primary keys are not nullable (and why would they be?).