diff --git a/src/racket/src/places.c b/src/racket/src/places.c
index 1a5dd4c5e7..e8042d57da 100644
--- a/src/racket/src/places.c
+++ b/src/racket/src/places.c
@@ -1047,7 +1047,7 @@ Scheme_Object *scheme_places_deep_copy_worker(Scheme_Object *so, Scheme_Hash_Tab
           }
         }
 
-        nprefab_key = scheme_places_deep_copy_worker(SCHEME_CDR(stype->prefab_key), ht, copy);
+        nprefab_key = scheme_places_deep_copy_worker(stype->prefab_key, ht, copy);
 
         if (copy) {
           new_so = scheme_make_serialized_struct_instance(nprefab_key, size);
@@ -1073,16 +1073,13 @@ Scheme_Object *scheme_places_deep_copy_worker(Scheme_Object *so, Scheme_Hash_Tab
         Scheme_Serialized_Structure *st = (Scheme_Serialized_Structure*)so;
         Scheme_Struct_Type *stype;
         Scheme_Structure *nst;
-        Scheme_Object *key;
         intptr_t size;
         int i = 0;
       
         size = st->num_slots;
+        stype = scheme_lookup_prefab_type(SCHEME_CDR(st->prefab_key), size);
 
-        key = scheme_places_deep_copy_worker(st->prefab_key, ht, copy);
-        
         if (copy) {
-          stype = scheme_lookup_prefab_type(key, size);
           new_so = scheme_make_blank_prefab_struct_instance(stype);
           nst = (Scheme_Structure*)new_so;
         } else
diff --git a/src/racket/src/struct.c b/src/racket/src/struct.c
index ea34402299..9676944783 100644
--- a/src/racket/src/struct.c
+++ b/src/racket/src/struct.c
@@ -120,6 +120,9 @@ static Scheme_Object *struct_to_vector(int argc, Scheme_Object *argv[]);
 static Scheme_Object *prefab_struct_key(int argc, Scheme_Object *argv[]);
 static Scheme_Object *make_prefab_struct(int argc, Scheme_Object *argv[]);
 static Scheme_Object *prefab_key_struct_type(int argc, Scheme_Object *argv[]);
+#ifdef MZ_USE_PLACES
+static Scheme_Object *convert_prefab_key_to_external_form(Scheme_Object *key);
+#endif
 
 static Scheme_Object *struct_setter_p(int argc, Scheme_Object *argv[]);
 static Scheme_Object *struct_getter_p(int argc, Scheme_Object *argv[]);
@@ -2798,7 +2801,13 @@ Scheme_Object *scheme_prefab_struct_key(Scheme_Object *so)
     s = (Scheme_Structure *)SCHEME_CHAPERONE_VAL((Scheme_Object *)s);
   
   if (SCHEME_STRUCTP(((Scheme_Object *)s)) && s->stype->prefab_key) {
-    return SCHEME_CDR(s->stype->prefab_key);
+    Scheme_Object *prefab_key;
+    prefab_key = SCHEME_CDR(s->stype->prefab_key);
+#ifdef MZ_USE_PLACES
+    return convert_prefab_key_to_external_form(prefab_key);
+#else
+    return prefab_key;
+#endif
   }
   
   return scheme_false;
@@ -3957,6 +3966,8 @@ Scheme_Struct_Type *scheme_make_prefab_struct_type_raw(Scheme_Object *base,
   struct_type->num_islots = num_fields + (parent_type ? parent_type->num_islots : 0);
   struct_type->name_pos = depth;
   struct_type->inspector = scheme_false;
+  //Scheme_Object *accessor *mutator;
+  //Scheme_Object *prefab_key;
   struct_type->uninit_val = uninit_val;
   struct_type->props = NULL;
   struct_type->num_props = 0;
@@ -3977,12 +3988,19 @@ static Scheme_Struct_Type *scheme_make_prefab_struct_type(Scheme_Object *base,
                                                           Scheme_Object *uninit_val,
                                                           char *immutable_array)
 {
-  return scheme_make_prefab_struct_type_raw(base,
-                                            parent,
-                                            num_fields,
-                                            num_uninit_fields,
-                                            uninit_val,
-                                            immutable_array);
+#ifdef MZ_USE_PLACES
+/*
+  return scheme_make_prefab_struct_type_in_master
+*/
+#else
+#endif
+  return scheme_make_prefab_struct_type_raw
+         (base,
+          parent,
+          num_fields,
+          num_uninit_fields,
+          uninit_val,
+          immutable_array);
 }
 
 static Scheme_Object *_make_struct_type(Scheme_Object *base,
@@ -4620,7 +4638,19 @@ static Scheme_Object *make_prefab_key(Scheme_Struct_Type *type)
     if (!SCHEME_NULLP(stack))
       key = scheme_make_pair(scheme_make_integer(icnt), key);
 
+/*symbols aren't equal?  across places now*/
+#if defined(MZ_USE_PLACES)
+    if (SCHEME_SYMBOLP(type->name)) {
+      Scheme_Object *newname;
+      newname = scheme_make_sized_offset_byte_string((char *)type->name, SCHEME_SYMSTR_OFFSET(type->name), SCHEME_SYM_LEN(type->name), 1);
+      key = scheme_make_pair(newname, key);
+    }
+    else {
+       scheme_arg_mismatch("make_prefab_key", "unknown type of struct name", type->name);
+    }
+#else
     key = scheme_make_pair(type->name, key);
+#endif
 
     if (SCHEME_PAIRP(stack)) {
       type = (Scheme_Struct_Type *)SCHEME_CAR(stack);
@@ -4673,6 +4703,29 @@ static char *mutability_data_to_immutability_data(int icnt, Scheme_Object *mutab
   return immutable_array;
 }
 
+#ifdef MZ_USE_PLACES
+static Scheme_Object *convert_prefab_key_to_external_form(Scheme_Object *key)
+{
+  Scheme_Object *l;
+  Scheme_Object *nl;
+
+  if (SCHEME_SYMBOLP(key)) return key;
+  if (SCHEME_BYTE_STRINGP(key))
+    return scheme_intern_exact_symbol(SCHEME_BYTE_STR_VAL(key), SCHEME_BYTE_STRLEN_VAL(key));
+
+  nl = scheme_null;
+  for (l = key; SCHEME_PAIRP(l); l = SCHEME_CDR(l)) {
+    Scheme_Object *a;
+    a = SCHEME_CAR(l);
+    if (SCHEME_BYTE_STRINGP(a))
+     a = scheme_intern_exact_symbol(SCHEME_BYTE_STR_VAL(a), SCHEME_BYTE_STRLEN_VAL(a));
+    nl = scheme_make_pair(a, nl);
+  }
+
+  return scheme_reverse(nl);
+}
+#endif
+
 Scheme_Struct_Type *scheme_lookup_prefab_type(Scheme_Object *key, int field_count)
 {
   Scheme_Struct_Type *parent = NULL;
@@ -4680,8 +4733,19 @@ Scheme_Struct_Type *scheme_lookup_prefab_type(Scheme_Object *key, int field_coun
   int ucnt, icnt;
   char *immutable_array = NULL;
 
+/*symbols aren't equal?  across places now*/
+#if defined(MZ_USE_PLACES)
+  if (SCHEME_SYMBOLP(key)) {
+    Scheme_Object *newname;
+    newname = scheme_make_sized_offset_byte_string((char*)key, SCHEME_SYMSTR_OFFSET(key), SCHEME_SYM_LEN(key), 1);
+    key = scheme_make_pair(newname, scheme_null);
+  }
+  if (SCHEME_BYTE_STRINGP(key))
+    key = scheme_make_pair(key, scheme_null);
+#else
   if (SCHEME_SYMBOLP(key))
     key = scheme_make_pair(key, scheme_null);
+#endif
 
   if (scheme_proper_list_length(key) < 0)
     return NULL;
@@ -4755,9 +4819,21 @@ Scheme_Struct_Type *scheme_lookup_prefab_type(Scheme_Object *key, int field_coun
     a = SCHEME_CAR(key);
     key = SCHEME_CDR(key);
 
+/*symbols aren't equal?  across places now*/
+#if defined(MZ_USE_PLACES)
+    if (SCHEME_SYMBOLP(a)) {
+      name = a;
+    }
+    else if (SCHEME_BYTE_STRINGP(a))
+      name = scheme_intern_exact_symbol(SCHEME_BYTE_STR_VAL(a), SCHEME_BYTE_STRLEN_VAL(a));
+    else
+      return NULL;
+#else
     if (!SCHEME_SYMBOLP(a))
       return NULL;
     name = a;
+#endif
+
 
     immutable_array = mutability_data_to_immutability_data(icnt + ucnt, mutables);
 
@@ -4765,10 +4841,10 @@ Scheme_Struct_Type *scheme_lookup_prefab_type(Scheme_Object *key, int field_coun
       return NULL;
 
     parent = scheme_make_prefab_struct_type(name,
-                                            (Scheme_Object *)parent,
-                                            icnt, ucnt,
-                                            uninit_val,
-                                            immutable_array);
+                                     (Scheme_Object *)parent,
+                                     icnt, ucnt,
+                                     uninit_val,
+                                     immutable_array);
     
   }