Nested Base classes

[llee]

I'm trying derive a class from a nested base class. The programs' structure is 
as follows:

class A
{
     class B
     {
     }
}

class C : A
{
     class D : B
     {
     }
}

I'm using version 2.014 of the dmd compiler, and the above fails. The compiler 
error reports that B is nested in class A and not C. Does anyone know a work 
around?