m_hWnd

Hi,
This is the second time I ask this question. In my application, I create a float frame window which is derived from (Stingray OT50) SECFDIFrame. Within the frame window, I create one ScrollView and one Control bar(derived from SECControlBar). Within the control bar is a list control derived from CListCtrl. The problem is when I want to insert a column or item into the list, assertion failed. m_hWnd is not null, but is is not the window get from GetSafeHwnd(). That means the window with the handle is not found.
Does any one know how to control m_hWnd? Do you know how to solve my problem? Your help will be greately appreciated.

Yusheng