I was able to fix the problem by changing my extconf.rb to:

    require 'mkmf'

    dir_config('gamer')
    have_library("SDL", "SDL_Init")
    have_header("SDL/SDL.h")
    pkg_config("sdl")
    create_makefile('gamer')

However, I don't know *WHY* it works. The pkg_config seems to be the 
crucial line.
I just went through other people's extconf.rb files and guessed the 
"sdl" value.
Any help would be appreciated, since there seems to be no documentation 
about
pkg_config...

Wim

-- 
Wim Vander Schelden
Bachelor Computer Science, University Ghent

http://nanoblog.ath.cx
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