Prevent property page size change at dynamically (runtime)

Question

I developed (ATL)ActiveX control which used to launched by 3rd party applications. My control has CProperySheet as a child, and which has few property pages. Once control created, i creating instance of CProperySheet, adding property pages to sheet and setting sheet window size to fit control size. In the propery sheet i have three buttons which is appears bottom of the active page.

whenever control size changed i try to set sheet and CTabCtrl size (but not page size) to fit control size dynamically. Problem is whenever sheet size changed property page size also changed automatically to fit sheet size(may be inside MFC code), so that buttons are not appearing in screen. I need to set propery page size to fixed, should not change dynamically.

Thanks,