Corrected a bug reported by hakzsam.

diff --git a/p02.lisp b/p02.lisp
index b2793db..2c55183 100644
--- a/p02.lisp
+++ b/p02.lisp
@@ -13,7 +13,7 @@ P02 (*) Find the last but one box of a list.
     ((endp list)                (error "Empty list"))
     ((endp (rest list))         (error "List too short"))
     ((endp (rest (rest list)))  list)
-    (t                          (my-last (rest list)))))
+    (t                          (my-but-last (rest list)))))


 ;; The efficient, iterative solution: