Linux QueryBuilder error

I have tracked down the QueryBuilder error, and it's not a wxWindows
error, per se.  The problem lies in the frmQueryBuilder::OnSize() event
handler.  Basically, the QueryBuilder form receives the OnSize event
*before* the form has been created.  Here is a thread from the
wxWindows list, discussing a similar problem a user had with a Windows
application:

http://lists.wxwindows.org/archive/wx-users/msg05277.html

Our situation is a bit different, because the code called by
frmQueryBuilder::OnSize is wxWindows code, and not custom code,
but....here is the problem.  In src/generic/laywin.cpp (from
wxWindows), the LayoutMDIFrame() function, calls the following code:

wxWindow* clientWindow = frame->GetClientWindow();

rect = event.GetRect();

clientWindow->SetSize(rect.x, rect.y, rect.width, rect.height);

Basically, frame->GetClientWindow() returns NULL, causing SetSize
(which is a macro) to cause a segfault in DoSetSize(clientWindow,
etc.).  The variable 'frame' is passed to LayoutMDIFrame by our code:
LayoutMDIFrame(this).
frame->GetClientWindow() is indeed null as frame->m_clientWindow = 0x0.
  I am looking for a solution to the problem, but I wanted to send it to
the list in case someone could fix it faster than I could.

ahp