In testdyngl.c the event type was being anded (&) with SDL_KEYDOWN and if the result was none zero the program was quiting. This is very weird because it was working earlier this week. I added some more trace code to SDL_x11events.c In SDL_X11opengl.c I modified SDL_GL_GetSwapInterval() so that it returns a pretty good value even if you have the SGI swap extension instead of the MESA swap extension. I just saved the value you set and return it too you.

/*
 *  libsdlmain_prefix.h
 *  SDLTest
 *
 *  Created by Darrell Walisser on Wed Aug 06 2003.
 *  Copyright (c) 2003 __MyCompanyName__. All rights reserved.
 *
 */

#include <Cocoa/Cocoa.h>
#include <Carbon/Carbon.h>
#include "SDL.h"
#include "SDLMain.h"