Another bug in function overloading?

[Domain via Digitalmars-d-learn]

module test;

public interface I
{
    void foo();
    void foo(int);
}
public abstract class A : I
{
    public void bar()
    {
        foo();
    }

    public void foo(int i)
    {
    }
}

public class C : A
{
    public void foo()
    {
    }

    public void bar2()
    {
        foo(1);
    }
}

Error: function test.A.foo (int i) is not callable using argument 
types ()
Error: function test.C.foo () is not callable using argument 
types (int)