Advising forward-char not working properly

[Milan Zamazal <pdm@zamazal.org>]

In GNU Emacs 21.3.2 (i386-pc-linux-gnu, X toolkit, Xaw3d scroll bars)
 of 2003-06-03 on blackbird, modified by Debian

When I advise the function forward-char or backward-char, the advice is
not invoked if the function is called via its key binding.

Try to evaluate the following in *scratch*:

  (defadvice forward-char (after foo activate)
    (message "Advice called"))

Then type `C-f' in some buffer -- the advice isn't called.

Now try `M-x forward-char' -- the advice is called as expected.

I think this is a bug.  self-insert-command seems to have a similar
problem.