[plt-scheme] libmzgc.a, libmzscheme.a on Mac OS X?

Folks,

I'm trying to compile Sergey Khorev's MzVim, but gcc complains that 
libmzgc.a and libmzscheme.a are unavailable. I see that they are not in 
/Applications/PLT Scheme v206/lib subdirectory, but mzdyn.o is. (I used 
the Mac OS X installer for DrScheme.)

Do I need to download and compile the source? Which flags do I need to 
set? Any help would be greatly appreciated; I can't find any hints on 
the web.

Thank you,

Michael Manti