Caption Bars

I want to control the drawing of the control buttons in a caption. (ie the close, minimize, maximize buttons)

The problem is that I can not find the message that draws these buttons. They automatically get drawn anytime the frame window receives a WM_NCLBUTTONDOWN or a WM_SETCURSOR message. If I intercept these messages I can prevent the buttons from being drawn. But I then have to handle these messages myself, which I'd really like to avoid doing.

I can disable the buttons by altering the style of the window and then draw them myself and handle the WM_NCHITTEST. But these is more of a hack than a good solution.

Is there some style, windows message, or anything I can do to control the drawing of these buttons?