RAD Studio 2010 C++Nuilder 和 Delphi 混合编程,该怎么处理

RAD Studio 2010 C++Nuilder 和 Delphi 混合编程
Form1 为CBuilder(VCL Form Application), Form2为Delphi(Form Delphi)  

Form1 里 Use Unit / Unit2.pas(Header)
Form2 里Use Unit /应该怎么来<Unit1.cpp (ingterface)这样一use,编译,有errors>



------解决方案--------------------
C++Builder& delphi共存;C++Builder工程调用delphi窗体 
C/C++ code

#include <vcl.h>
#pragma hdrstop

#include "Unit1.h"
#include "Unit2.hpp" //添加pas 编译生成的 .hpp文件
//---------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
//---------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
    : TForm(Owner)
{
  ShowMessage(Form2->Str);
}