How to stop Maximized app being restored?

Hi,

I have an SDI app with a title bar, but no system menu or min, max, close buttons. I start the app maximized, and I don't want the user to be able to change this. However, when the user double clicks the title bar, the Main window is restored. Double clicking again does not maximize it. How can I stop this so it always stays maximized?

thanks,

uniken