hi Ted, > scons RacketPrefix=/usr/local/racket-5.1.1_32 ADDONS=0 as far as i remember scons does not take the environment variables into account. try it like this: scons RacketPrefix=/usr/local/racket-5.1.1_32 CCFLAGS=" -arch i386 " LDFLAGS=" -arch i386 " ADDONS=0 best, gabor