Problem with CPaneFrameWnd and CDockablePane

Hi, I'm struggling with a serious problem with a CPaneFrameWnd and CDockablePane.

This is the scenario: I have a CDockablePane derived class and a CPaneFrameWnd derived class; in the OnCreate() of CDockablePane I call SetMiniFrameRTC(RUNTIME_CLASS(CMyPane)); (CMyPane is derived from CPaneFrameWnd), and also in ctor I use m_pMiniFrameRTC = RUNTIME_CLASS(CMyPane);

My CMyPane has an override of OnNcHitTest(CPoint) to manage the cursor in order to get my CDockablePane not resizable.

I notice that the first time I create the CDockablePane, and passing mouse over my pane, the OnNcHitTest() method is not called, BUT after I dock and undock the pane (or the pane start in docked mode) the OnNcHitTest() works correctly.

I tested it with VS2008 and VS2012 and I obtain the same behaviour! 

What's the matter? How I can get the correct OnNcHitTest() method called ALSO at the first time??

Thanks in advance.

Paolo