Invalid constructor generated in the example class of a subclass

I have the following in the business model:

class Person {
 string name
 maxlength 50;
}

class Employee inherits Person {
 boolean active default true;
}

This gives a compile error in EmployeeExample: "Implicit constructor Employee() is undefined". EmployeeExample.java contains the following generated constructor:

 public EmployeeExample() {
 activateValidation(false);
 actief = null;
 }

There is no default constructor in Person, because Person has non-nullable fields. The problem will go away if I define an extra string property in Employee, or if I define Person.name to be nullable.