Fixed bug #713 Don't clamp the mouse coordinates to the video surface size, instead clamp them to the last known window size. This allows users to get the correct mouse coordinates even if they don't call SDL_SetVideoMode() in response to an SDL_VIDEORESIZE event (used as a hack to retain the OpenGL context on Windows and Linux after a window resize)

The AmigaOS code has been removed from SDL, since it had been broken for a
 long time and had a few bits of fairly invasive code #ifdef'd into the
 SDL core.

However, there is an OS4 version of SDL here:
   http://www.rcdrummond.net/amiga/index.html

And a MorphOS version here:
   http://www.lehtoranta.net/powersdl/

--ryan.