In order to compile Mail for your machine, you must make sure
that you have the right versions of "local.c" and "local.h"
These have the naming convention that the non-prefixed version is
a copy of a real version and may be clobbered.  The real version are
prefixed with single characters with the following scheme:

	v	Vax 11 version (really version 7)
	c	EECS Cory hall version
	i	Ingres (virgin version 6)

You also will need the correct makefile.  These are named with suffixes:
.vax for Vax, .cory for Cory, and .ing for ingres.

Note that if you are non Version 7 you will need _stat.c which makes
the Version 6 stat() call look like that of Version 7.