Dedocking and redocking messups

I have a Lenovo Thinkpad T61, with a docking station. When I pop it off the dock, and then later put it back, sometimes the screen does weird things, like it won't allow me to move windows to the right 1/8 of the screen. The laptop is widescreen, the monitor is not. I suppose that's the reason. I've figured out a solution in just doing the Fn-F7 before I undock. I think that gets the display in the right mode, and then it can switch back later when I dock, and it works again.