diff --git a/collects/scheme/private/class-internal.ss b/collects/scheme/private/class-internal.ss
index 26611adb16..9d1dc06670 100644
--- a/collects/scheme/private/class-internal.ss
+++ b/collects/scheme/private/class-internal.ss
@@ -211,6 +211,9 @@
 
 (define-values (prop:unwrap object-unwrapper)
   (let-values ([(prop:unwrap pred acc) (make-struct-type-property 'prop:unwrap)])
+    ;; Instead of using the accessor if it has prop:unwrap, just use the unwrapper
+    ;; from wrapper-object directly, since we know it must be a wrapped object.
+    ;; (The accessor will just give us that anyway.)
     (values prop:unwrap (λ (o) (if (pred o) (wrapper-object-wrapped o) o)))))
 
 ;;--------------------------------------------------------------------
diff --git a/src/mzscheme/utils/xcglue.c b/src/mzscheme/utils/xcglue.c
index 2454fe7777..f170640f23 100644
--- a/src/mzscheme/utils/xcglue.c
+++ b/src/mzscheme/utils/xcglue.c
@@ -463,7 +463,7 @@ int objscheme_is_a(Scheme_Object *o, Scheme_Object *c)
 Scheme_Object *objscheme_unwrap(Scheme_Object *obj, Scheme_Object *c)
 {
   Scheme_Object *s[1], *unwrapper, *unwrap_prop;
-  Scheme_Class *cls = (Scheme_Class *)cls;
+  Scheme_Class *cls = (Scheme_Class *)c;
 
   if (!obj || !cls)
     return NULL;
@@ -471,6 +471,7 @@ Scheme_Object *objscheme_unwrap(Scheme_Object *obj, Scheme_Object *c)
   unwrap_prop = cls->unwrap_property;
   if(!unwrap_prop)
     return obj;
+
   unwrapper = scheme_struct_type_property_ref(unwrap_prop, (Scheme_Object *)obj);
   if (!unwrapper)
     return obj;