¡Malditos componentes!

[ElDuc]

Este es el código completo de la unidad:

Código Delphi [-]
unit _ieApplication;
interface
uses
  SysUtils, Classes, JfMain;
type
  TieData=Class(TPersistent)
    A:Integer;
    B:Integer;
    End;
Type
  TieApplication = class(TJfCApplication)
  private
    { Private declarations }
    vieData:TieData;
    Function rieData:TieData;
    Procedure wieData(V:TieData);
  protected
    { Protected declarations }
  public
    { Public declarations }
    Constructor Create(AOwner:TComponent) Overload;
    Destructor Destroy; Overload;
  published
    { Published declarations }
    Property ieData:TieData Read rieData Write wieData;
  end;
procedure Register;
implementation
Constructor TieApplication.Create(Owner:TComponent);
Begin
Inherited;
vieData:=TieData.Create;
End;
Destructor TieApplication.Destroy;
Begin
ieData.Free;
Inherited;
End;
Function TieApplication.rieData:TieData;
Begin
Result.A:=vieData.A;
Result.B:=vieData.B;
End;
Procedure TieApplication.wieData(V:TieData);
Begin
vieData.A:=V.A;
vieData.B:=V.B;
End;
procedure Register;
begin
  RegisterComponents('ieCRON', [TieApplication]);
end;
end.

Y estos son los errores:
[Error] _ieApplication.pas(10): Published field 'A' not a class nor interface type
[Error] _ieApplication.pas(11): Published field 'B' not a class nor interface type

Yo no sé que quiere decir.