Probably your suggestion works, however I found 2 solutions:
1- In the document change the bool m_bAutodelete to False, and set back to True once I finish to replace.
2- I found a beautiful replaceview method in the splitter, It do everything for me automatically. I implemented this one. http://support.microsoft.com/kb/149257
PS: I tested the 1st solution as well, just to try.. and it also works.
PS2: I realized ReplaceView CPlitter method is not a native method of MFC CSplitter, I'm using a derivated CSplitter of CodeJock library and it offer this method.