How do you create a new MDI child frame when overriding OnFileNew

I am trying to create my own child windows from within my overriden OnFileNew() in an MDI application. When I start the app the default frame/view/doc comes up (which I have set to be a maximized window without a title bar). I have a menu selection that allows you to "split the view" which essentially sets a global boolean and calls my overriden OnFileNew() function. This function either creates the first view I mentioned or, when called with the boolean set to true, creates a static split view in a new child frame after deleting the old one. When it gets to this point the application bombs...... something about a user breakpoint being set. (it debugs into assembly INT 3 is the instruction) The split view is displayed before the app crashes. Does anyone have some suggestions on how to handle this? the MFC documentation talks about being able to create your own child frames instead of letting the framework do it.... but doesn't go into specifics. Please help!!!!

Tom