diff --git a/collects/redex/private/reduction-semantics.rkt b/collects/redex/private/reduction-semantics.rkt
index aa36b04a94..23ba5588f3 100644
--- a/collects/redex/private/reduction-semantics.rkt
+++ b/collects/redex/private/reduction-semantics.rkt
@@ -6,7 +6,7 @@
          "fresh.ss"
          "loc-wrapper.ss"
 	 "error.ss"
-         mzlib/trace
+         racket/trace
          racket/contract
          (lib "list.ss")
          (lib "etc.ss")
@@ -1660,12 +1660,20 @@
                        (log-coverage (cdr cache-ref))
                        (car cache-ref)])))]
                [ot (current-trace-print-args)]
+               [otr (current-trace-print-results)]
                [traced-metafunc (lambda (exp)
                                   (if (or (eq? (current-traced-metafunctions) 'all)
                                           (memq name (current-traced-metafunctions)))
                                       (parameterize ([current-trace-print-args
                                                       (λ (name args kws kw-args level)
-                                                        (ot name (car args) kws kw-args level))])
+                                                        (if (eq? not-in-cache (hash-ref cache exp not-in-cache))
+                                                            (display " ")
+                                                            (display "c"))
+                                                        (ot name (car args) kws kw-args level))]
+                                                     [current-trace-print-results
+                                                      (λ (name results level)
+                                                        (display " ")
+                                                        (otr name results level))])
                                         (trace-call name metafunc exp))
                                       (metafunc exp)))])
         traced-metafunc))
diff --git a/collects/redex/redex.scrbl b/collects/redex/redex.scrbl
index d1e7ce1605..0f736fe16a 100644
--- a/collects/redex/redex.scrbl
+++ b/collects/redex/redex.scrbl
@@ -1083,6 +1083,12 @@ Controls which metafunctions are currently being traced. If it is
 @racket['all], all of them are. Otherwise, the elements of the list
 name the metafunctions to trace. 
 
+The tracing looks just like the tracing done by the @racketmodname[racket/trace]
+library, except that the first column printed by each traced call indicate
+if this call to the metafunction is cached. Specifically, a @tt{c} is printed
+in the first column if the result is just returned from the cache and a
+space is printed if the metafunction call is actually performed.
+
 Defaults to @racket['()].
 
 }
diff --git a/collects/redex/tests/tl-test.rkt b/collects/redex/tests/tl-test.rkt
index 68fbd204c7..57f8ccc5a7 100644
--- a/collects/redex/tests/tl-test.rkt
+++ b/collects/redex/tests/tl-test.rkt
@@ -757,14 +757,28 @@
                      [current-traced-metafunctions 'all]
                      [print-as-expression #f])
         (term (f 1)))
-      (test (get-output-string sp) ">(f 1)\n<0\n"))
+      (test (get-output-string sp) "c>(f 1)\n <0\n"))
     
     (let ([sp (open-output-string)])
       (parameterize ([current-output-port sp]
                      [current-traced-metafunctions '(f)]
                      [print-as-expression #f])
         (term (f 1)))
-      (test (get-output-string sp) ">(f 1)\n<0\n")))
+      (test (get-output-string sp) "c>(f 1)\n <0\n"))
+    
+    
+    (define-metafunction empty-language
+      [(g (any)) ((g any) (g any))]
+      [(g 1) 1])
+    
+    (let ([sp (open-output-string)])
+      (parameterize ([current-output-port sp]
+                     [current-traced-metafunctions '(g)]
+                     [print-as-expression #f])
+        (term (g (1))))
+      (test (get-output-string sp) " >(g (1))\n > (g 1)\n < 1\nc> (g 1)\n < 1\n <(1 1)\n"))
+    
+    )
   
   (let ()
     (define-language var-lang [(x y z w) variable])