[fpc, mindfuck] Смешная ошибка

{$mode objfpc}{$h+} // FPC 2.4RC1
unit test_unit;
interface
type
  generic IEnumerable<A> = interface
    function Current: A;
    procedure MoveNext;
  end;
  generic Test<A> = class
    function GetEnumerator: specialize IEnumerable<A>;
  end;
implementation
function Test.GetEnumerator: specialize IEnumerable<A>;
begin
	result := nil;
end;
end.

  generic Test<A> = class
    procedure GetEnumerator(var e: specialize IEnumerable<A>);
  end;