Confirmed, the same error occurs for me. That's absurd.
EDIT: Scratch that, just add g_syscalls.o to the list and it should work (After you fix the extern "C" issue in that file the same way you did with vmMain in g_main.c)
Though eh, I'm getting a segfault as soon as the map loads - this may just be my mod though, I haven't tested on base.
EDIT: Base works...fine...
except when I connect with my windows client I get dropped to the console with "Shutting down OpenGL subsystem...ERROR: no shader files found"
EDIT: All works fine, just had to actually START the server with sv_pure 0
(As opposed to changing + restarting...odd yah)
Many thanks to TrippHop, Xycaleth, Subaru