(defpackage :one
  (:use :common-lisp)
)
(defpackage :two
  (:use :common-lisp)
)

(in-package :one)

(defclass foo () 
  ()
)

(defgeneric foo-method (x))

(defmethod foo-method ((x number)) (+ x 1))
(defmethod foo-method ((s string)) (format nil "foo ~A" s))

(defvar *x* (make-instance 'foo))

(in-package :two)

(defun bar (obj meth arg)
  (funcall (symbol-function (find-symbol (format nil "~A-~A" (symbol-name (class-name (class-of obj))) (string-upcase meth)) (find-package 'one))) arg)
)

;(print (bar one::*x* "Method" 1))
;(print (bar one::*x* "Method" "bar"))

;(defun find-orig-package)