Implement IDispEventSimpl eImpl Interface to Handle Event, Function calls two times

[shama]

Hi all,
I want to develop add-in for OUTLOOK, In that for event handling use IDispEventSimpl eImpl Interface, and declare handler function (fn) for the specified event using SINK_ENTRY_INFO , but whenever that particular event occurs my handler function gets call two times! why it happens so? I want to call it only single time....
MY code is.....

class ATL_NO_VTABLE CConnect :
public CComObjectRootE x<CComSingleThr eadModel>,
public CComCoClass<CCo nnect, &CLSID_Connect> ,
public IDispatchImpl<A ddInDesignerObj ects::_IDTExten sibility2, &AddInDesignerO bjects::IID__ID TExtensibility2 , &AddInDesignerO bjects::LIBID_A ddInDesignerObj ects, 1, 0>,
public IDispEventSimpl eImpl<1,CConnec t,&__uuidof(Out look::ExplorerE vents)>,
{
public:

BEGIN_SINK_MAP( CConnect)
SINK_ENTRY_INFO (1,__uuidof(Out look::ExplorerE vents),0xf002,o nFolderChange,& OnSimpleEventIn fo)
END_SINK_MAP()
public:
//type defination to avoid compilation 'ambigous call' errors
typedef IDispEventSimpl eImpl<1,CConnec t, &__uuidof(Outlo ok::ExplorerEve nts)> ExpEvents;

void __stdcall onFolderChange( );
}


Any idea about this, please suggest me...

Thanks & Regards,
Shyam