diff --git a/collects/srfi/63/63.ss b/collects/srfi/63/63.ss
index 373a126416..79a6e1706d 100644
--- a/collects/srfi/63/63.ss
+++ b/collects/srfi/63/63.ss
@@ -136,40 +136,43 @@
         (vector? obj)
         (my-array? obj)))
   
-  (define (s:equal? obj1 obj2)
-    (or (equal? obj1 obj2)
-        (and (box? obj1)
-             (box? obj2)
-             (s:equal? (unbox obj1)
-                       (unbox obj2)))
-        (and (pair? obj1)
-             (pair? obj2)
-             (s:equal? (car obj1) (car obj2))
-             (s:equal? (cdr obj1) (cdr obj2)))
-        (if (vector? obj1)
-            (and (vector? obj2)
-                 (equal? (vector-length obj1) (vector-length obj2))
-                 (let lp ((idx (sub1 (vector-length obj1))))
-                   (or (negative? idx)
-                       (and (s:equal? (vector-ref obj1 idx)
-                                      (vector-ref obj2 idx))
-                            (lp (sub1 idx))))))
-            ;; Not a vector
-            (or (and (array? obj1)
-                     (array? obj2)
-                     (equal? (array-dimensions obj1) (array-dimensions obj2))
-                     (s:equal? (array->vector obj1) (array->vector obj2)))
-                (and (struct? obj1)
-                     (struct? obj2)
-                     (let-values (((obj1-type obj1-skipped?)
-                                   (struct-info obj1))
-                                  ((obj2-type obj2-skipped?)
-                                   (struct-info obj2)))
-                       (and (eq? obj1-type obj2-type)
-                            (not obj1-skipped?)
-                            (not obj2-skipped?)
-                            (s:equal? (struct->vector obj1)
-                                      (struct->vector obj2)))))))))
+ (define (s:equal? obj1 obj2)
+   (or (equal? obj1 obj2)
+       (cond ((and (box? obj1)
+                   (box? obj2))
+              (s:equal? (unbox obj1)
+                        (unbox obj2)))
+             ((and (pair? obj1)
+                   (pair? obj2))
+              (and (s:equal? (car obj1) (car obj2))
+                   (s:equal? (cdr obj1) (cdr obj2))))
+             ((and (vector? obj1)
+                   (vector? obj2))
+              (and (equal? (vector-length obj1) (vector-length obj2))
+                   (let lp ((idx (sub1 (vector-length obj1))))
+                     (or (negative? idx)
+                         (and (s:equal? (vector-ref obj1 idx)
+                                        (vector-ref obj2 idx))
+                              (lp (sub1 idx)))))))
+             ((and (string? obj1)
+                   (string? obj2))
+              (string=? obj1 obj2))
+             ((and (array? obj1)
+                   (array? obj2))
+              (and (equal? (array-dimensions obj1) (array-dimensions obj2))
+                   (s:equal? (array->vector obj1) (array->vector obj2))))
+             ((and (struct? obj1)
+                   (struct? obj2))
+              (let-values (((obj1-type obj1-skipped?)
+                            (struct-info obj1))
+                           ((obj2-type obj2-skipped?)
+                            (struct-info obj2)))
+                (and (eq? obj1-type obj2-type)
+                     (not obj1-skipped?)
+                     (not obj2-skipped?)
+                     (s:equal? (struct->vector obj1)
+                               (struct->vector obj2)))))
+             (else #f))))
   
   (define (array-rank obj)
     (if (array? obj) (length (array-dimensions obj)) 0))