I just spent a hour and a half trying to figure out how you compile the example projects from the book Essential Math for Games and Interactive Applications (second edition) on Mac OS X 10.6. It seems that the new version of GCC included with 10.6 is stricter when it comes to following the C++ standard. For the posterity, here is how you compile them now:
On line 204 of /common/IVGraphics/OGL/IvRenderOGL.cpp, change GLvoid to void.
When compiling, use the following command instead of the one provided in README_MAXOS.txt:
make CFLAGS_EXT='-fvisibility-inlines-hidden -ffriend-injection' PLATFORM=OSX