[Mingw-cross-env-list] warning: "WIN32_LEAN_AND_MEAN" redefined

[Martin Gerhardy]

getting a bunch of these errors - what would be the best way to fix
them? another sed in the sdl.mk?

/home/mattn/Desktop/mingw-cross-env-2.12/usr/i686-pc-mingw32/include/SDL/SDL_opengl.h:30:1:
 warning: "WIN32_LEAN_AND_MEAN" redefined
In file included
from 
/opt/mingw-env/usr/bin/../lib/gcc/i686-pc-mingw32/4.4.0/../../../../i686-pc-mingw32/include/curl/curl.h:35,
                 from src/client/battlescape/../../common/http.h:30,
                 from src/client/battlescape/../../common/common.h:33,
                 from src/client/battlescape/../cl_renderer.h:28,
                 from src/client/battlescape/../client.h:32,
                 from src/client/battlescape/cl_particle.c:26:

greetings
martin