(getenv "TERM) always returns "dumb"

[Peter Heslin]

Due to a recent change in startup.el, (getenv "TERM") now always
returns "dumb":

;; Subprocesses of Emacs do not have direct access to the terminal, 
;; so unless told otherwise they should only assume a dumb terminal. 
    (setenv "TERM" "dumb")

So what is now the correct way for an Emacs customization to determine
the original value of this environment variable?

(For another person who was recently bitten by this change, see the
thread in comp.emacs entitled "emacs -nw and 256 colors in xterm".)

Peter