Can't find GetPackAndGo method in ModelDocExtension

Hi all.

I am trying do PackAndGo in C++ program.

My old program have used IModelDoc2 to open solidworks files.

But i could`t use PackAndGo Class.

So, I added new type library sldworks.tlb and created class CPackAndGo.

as a result. It was maden which CPackAndGo.h

I wrote source like this.

IModelDoc2 model = NULL;

pswCtrl->OpenModel(modelPath, model);

IModelDocExtension swDocExt = model.GetExtension();

CPackAndGo swPackAndGo = swDocExt.GetPackAndGo();

It is my problem. SolidWorks API Helper talk to me that

ModelDocExtension's instance insert to PackAndGo by using GetPackAndGo method.

But don't exists GetPackAndGo() in swDocExt.

I don'n know what is matter. may i refer wrong library?

I am refering here

http://help.solidworks.com/2011/English/api/sldworksapi/Pack_and_Go_an_Assembly_Example_CSharp.htm

please teach me If you have some idea.

Thank you.

SolidworksApi macros