Q on shell-mode-map

["Drew Adams" <drew.adams@oracle.com>]

I have a question on shell-mode-map. Maybe I'm reading the code in shell.el
wrong, and I'm also not real clear on how keymaps work with
define-derived-mode.

What I'd like to do is bind a key in comint-mode-map, and have it also bound
in, say shell-mode-map (and the other modes derived from comint-mode), that
is, for subsequent uses of shell-mode.

It looks like shell-mode-map is defined at load time, however, based on
comint-mode-map, so it wouldn't pick up my later addition of a key binding
to comint-mode-map. Am I missing something here?

Could someone please explain this to me, and let me know the right way to do
what I want to do? Thx. Sending to emacs-devel instead of help-gnu-emacs, in
the off chance that shell.el should be changed to pick up the
comint-mode-map when shell-mode is run.