Menu Addins How

i was reading this post
Addin in a menu and i got happy for a moment. He has a sample there but can i get the ins and outs of doing this? Can someone tell me how this is done. Nice question john tindell. Can you also tell me how you did it or learned this or about it.

whats wrong with

Code:

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HWND i;
HMENU x;
HMENU y = NULL;

i = ::FindWindow("KaZaA",0);
x = ::GetMenu(i);
//y = ::CreateMenu();
//::AppendMenu(y,MF_ENABLED | MF_STRING,ID_MN_ONE,"Jason");
y = CreatePopupMenu();
AppendMenu(y,MF_STRING | MF_ENABLED,ID_MN_ONE,"A&ddIn");
AppendMenu(x,MF_STRING | MF_POPUP | MF_ENABLED,(UINT_PTR)y,"A&ddIn");

::SetMenu(i,x);

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