How to put the top view to bottom in OnOpenDocument()

I have a multidoc-multiview application. I have to make the default view active before
OnOpenDocument() returns to MFC standard processing. This behaviour is not desirable though,
so I have to put this view back to bottom again after the document is opened. There is a function
CMDIFrameWnd::MDINext() which seems to be able to do the job, however I do not know
where to implement it as there is no more message to process after OnOpenDocument() returns.
Or there may be other ways to achieve the same result.
Could you MFC gurus give me some advice?

Thanks a lot in advance.