CGAL users discussion list

Dear cgal discussion group,

I try to compile my first cgal program under MAC os x and I get the following 
error: 

peter-noels-computer:~/Documents/c++ projects/region_define pbnoel$ make
g++ -c  -I /usr/local/CGAL-3.3/include -Wall -frounding-math 
'-I/usr/local/CGAL-3.3/include/CGAL/config/i386_Darwin-8.10_g++-4.0.1' 
'-I/usr/local/CGAL-3.3/include' -I/usr/local/boost_1_34_0 
-I/usr/X11R6/include -DCGAL_USE_F2C  -L 
/usr/local/CGAL-3.3/lib/i386_Darwin-8.10_g++-4.0.1/libCGAL.a  sweep_line.cpp
g++ -o region define_region.o ImageIO.o ImageGrayscale.o sweep_line.o
/usr/bin/ld: Undefined symbols:
CGAL::assertion_fail(char const*, char const*, int, char const*)
CGAL::precondition_fail(char const*, char const*, int, char const*)
collect2: ld returned 1 exit status
make: *** [region] Error 1


I'm thinking may did something wrong in my makefile. But I'm not sure. Thank 
you for all your help...

---peter