yes, I broke it

It seems like xargs on OS X doesn't like -i, older linux versions (like the vmware image seems to contain) don't like -I. --replace works on linux only ...
You can try by replacing two lines in manual/Makefile
- @find * -type d \! -regex '.*\.svn.*' | xargs -I {} mkdir -p $(OBJDIR)/{}
- @find * -type f \! -regex '.*\.svn.*' | xargs -I {} cp {} $(OBJDIR)/{}
+ find * -type d \! -regex '.*\.svn.*' -exec mkdir -p $(OBJDIR)/{} \;
+ find * -type f \! -regex '.*\.svn.*' -exec cp {} $(OBJDIR)/{} \;
I'll recheck this when I come home tonight and change it if it works as expected. ATM I can only access a really outdated linux box.