The only thing I can think of is this:
Right-click on the Layout/Model tabs if you have the old-style ones visible, or if not, right-click on the new "Quick View Layouts" button in C3D 2009, and select "Move or Copy". This should call up the dialog to move layouts, as seen in the attached image. Move the layouts around, so they are in a different order.
I have seen this clear up problems with layouts. Unfortunately, not this particular problem, so I don't know if this will help you or not. But it's the only "trick" I can think of that has cleared up layout problems for me.
