diff --git a/ATL/Pooh/objects.atl b/ATL/Pooh/objects.atl
index b6d56fc..d7643be 100644
--- a/ATL/Pooh/objects.atl
+++ b/ATL/Pooh/objects.atl
@@ -17,6 +17,7 @@
 	|  Mr SANDERS  |
 	+--------------+
 	"
+	fixed
 
 define-item "Piglet's sign"
 	description "
@@ -25,6 +26,7 @@
 	|   TRESPASSERS  W >
 	|_________________<
 	"
+	fixed
 
 define-item "North Pole"
 	description "

diff --git a/ATL/Pooh/objects.atl b/ATL/Pooh/objects.atl
index b6d56fc..d7643be 100644
--- a/ATL/Pooh/objects.atl
+++ b/ATL/Pooh/objects.atl
@@ -17,6 +17,7 @@
 	|  Mr SANDERS  |
 	+--------------+
 	"
+	fixed
 
 define-item "Piglet's sign"
 	description "
@@ -25,6 +26,7 @@
 	|   TRESPASSERS  W >
 	|_________________<
 	"
+	fixed
 
 define-item "North Pole"
 	description "
diff --git a/lisp/game-objects.lisp b/lisp/game-objects.lisp
index c5272e7..abdf8fe 100644
--- a/lisp/game-objects.lisp
+++ b/lisp/game-objects.lisp
@@ -54,6 +54,7 @@
 	(description "")
 	(cost 0)
 	(weapon)
+	(fixed)
 	;(pickup-hook NIL)
 	;(drop-hook NIL)
 	(ability NIL)) ;XXX Remove abilities again?

diff --git a/ATL/Pooh/objects.atl b/ATL/Pooh/objects.atl
index b6d56fc..d7643be 100644
--- a/ATL/Pooh/objects.atl
+++ b/ATL/Pooh/objects.atl
@@ -17,6 +17,7 @@
 	|  Mr SANDERS  |
 	+--------------+
 	"
+	fixed
 
 define-item "Piglet's sign"
 	description "
@@ -25,6 +26,7 @@
 	|   TRESPASSERS  W >
 	|_________________<
 	"
+	fixed
 
 define-item "North Pole"
 	description "
diff --git a/lisp/game-objects.lisp b/lisp/game-objects.lisp
index c5272e7..abdf8fe 100644
--- a/lisp/game-objects.lisp
+++ b/lisp/game-objects.lisp
@@ -54,6 +54,7 @@
 	(description "")
 	(cost 0)
 	(weapon)
+	(fixed)
 	;(pickup-hook NIL)
 	;(drop-hook NIL)
 	(ability NIL)) ;XXX Remove abilities again?
diff --git a/lisp/ui.lisp b/lisp/ui.lisp
index 36cd234..c8bc4a9 100644
--- a/lisp/ui.lisp
+++ b/lisp/ui.lisp
@@ -247,16 +247,15 @@
 	(let* ((choice (choose-option (append (npc-sells npc) (list "None"))))
 			  (item (get-game-object 'item choice))
 			  (cost (if item (item-cost item) NIL)))
+		;; TODO The cost should be displayed alongside every item.
 		(cond ((equalp choice "None") NIL)
-			;; XXX Do we have to insure that every object referenced by the
-			;; world exists, or is that the responsibility of the person
-			;; who writes the ATL code?
 			((not item)
 				(format t "~&This object does not exist!")
-				(format t "(Talk to the world creator)")
+				(format t "~&(This is a bug in the game world.)")
 				NIL)
 			((< (player-money player) cost)
-				(format t "~&You do not have enough money!"))
+				(format t "~&This costs ~S. You do not have enough money!"
+					cost))
 			((y-or-n-p "Buy ~A for ~S?" choice cost)
 				(decf (player-money player) cost)
 				(set-object-attribute player 'item choice)
@@ -272,12 +271,14 @@
 	(let ((place (get-game-object 'place (player-place player)))
 			 (item (get-game-object 'item item-name)))
 		(if (member item-name (place-item place) :test #'equalp)
-			(progn
-				;; XXX Shouldn't the item's function be executed here?
-				;; Or should item functions be disabled entirely?
-				(set-object-attribute player 'item item-name)
-				(remove-object-attribute place 'item item-name)
-				(format t "~&You have picked up: ~A" item-name))
+			(if (item-fixed item)
+				(format t "~&You cannot pick this up!")
+				(progn
+					;; XXX Shouldn't the item's function be executed here?
+					;; Or should item functions be disabled entirely?
+					(set-object-attribute player 'item item-name)
+					(remove-object-attribute place 'item item-name)
+					(format t "~&You have picked up: ~A" item-name)))
 			(format t "~&Sorry, this item is not here!"))))
 
 (defun drop (player &optional item)