Macrolet

[bha <@ada3.ca.boeing.com:bha@gumby.boeing.com>]

I am trying to use MACROLET to hide the global definition of a macro
name with my own version.  I want to define a function that accepts a
form to be evaluated in the lexical environment of the MACROLET.

I know that I must have to deal with the environment argument to
macroexpand-1 but can't seem to grok it.  The following never seems to
expand the form correctly.

(defun foo (form)
  (macrolet ((my-macro (&rest x)
		 `(funcall #'+ ,@x)))

    (format t "~&Form: ~a~%Expansion: ~a~&" form (macroexpand-1 form))
    (eval (macroexpand-1 form))
    ))

=> (foo '(my-macro 1 2 3))

This should return 6 but the eval causes an undefined function error
since the expansion is never really done.

So, how do I get macroexpand-1 to recognize the lexical environment
that the my-macro macro is defined in?