diff --git a/src/mzscheme/gc2/newgc.c b/src/mzscheme/gc2/newgc.c
index db43c7645f..8bf80d1888 100644
--- a/src/mzscheme/gc2/newgc.c
+++ b/src/mzscheme/gc2/newgc.c
@@ -1547,6 +1547,11 @@ void GC_switch_out_master_gc() {
   }
 }
 
+void GC_switch_in_master_gc() {
+  GC_set_GC(MASTERGC);
+}
+
+
 void GC_gcollect(void)
 {
   NewGC *gc = GC_get_GC();
diff --git a/src/mzscheme/src/module.c b/src/mzscheme/src/module.c
index ac0696704c..d89f04f903 100644
--- a/src/mzscheme/src/module.c
+++ b/src/mzscheme/src/module.c
@@ -2716,7 +2716,7 @@ static Scheme_Object *module_path_index_join(int argc, Scheme_Object *argv[])
   return scheme_make_modidx(argv[0], argv[1], scheme_false);
 }
 
-Scheme_Object *scheme_intern_resolved_module_path(Scheme_Object *o)
+Scheme_Object *scheme_intern_resolved_module_path_worker(Scheme_Object *o)
 {
   Scheme_Object *rmp;
   Scheme_Bucket *b;
@@ -2744,6 +2744,21 @@ Scheme_Object *scheme_intern_resolved_module_path(Scheme_Object *o)
   return return_value;
 }
 
+Scheme_Object *scheme_intern_resolved_module_path(Scheme_Object *o)
+{
+#if defined(MZ_USE_PLACES) && defined(MZ_PRECISE_GC)
+  mz_proc_thread *self;
+  self = proc_thread_self;
+  if ( scheme_master_proc_thread && scheme_master_proc_thread != proc_thread_self ) {
+    int return_msg_type;
+    void *return_payload;
+    pt_mbox_send_recv(scheme_master_proc_thread->mbox, 1, o, self->mbox, &return_msg_type, &return_payload);
+    return (Scheme_Object*) return_payload;
+  }
+#endif
+  return scheme_intern_resolved_module_path_worker(o);
+}
+
 static Scheme_Object *resolved_module_path_p(int argc, Scheme_Object *argv[])
 {
   return (SCHEME_MODNAMEP(argv[0])
diff --git a/src/mzscheme/src/places.c b/src/mzscheme/src/places.c
index 8f2d38aa95..48b9fc0e62 100644
--- a/src/mzscheme/src/places.c
+++ b/src/mzscheme/src/places.c
@@ -218,15 +218,44 @@ static void *place_start_proc(void *data_arg) {
   return scheme_true;
 }
 
-static void *master_scheme_place(void *data) {
 #ifdef MZ_PRECISE_GC
-#endif
+static void *master_scheme_place(void *data) {
+  GC_switch_in_master_gc();
+  while(1) {
+    int recv_type;
+    void *recv_payload;
+    pt_mbox *origin;
+    Scheme_Object *o;
+
+    pt_mbox_recv(scheme_master_proc_thread->mbox, &recv_type, &recv_payload, &origin);
+    switch(recv_type) {
+      case 1:
+        o = scheme_intern_resolved_module_path_worker((Scheme_Object *)recv_payload);
+        pt_mbox_send(origin, 2, (void *) o, NULL);
+        break;
+      case 3:
+        break;
+      case 5:
+        break;
+    }
+  }
   return NULL;
 }
 
 void spawn_master_scheme_place() {
+  mz_proc_thread *thread;
+  pt_mbox *mbox;
+  unsigned int threadid;
+  thread    = (mz_proc_thread*)malloc(sizeof(mz_proc_thread));
+  mbox      = pt_mbox_create();
+  threadid  = mz_proc_thread_self();
+  thread->threadid  = threadid;
+  thread->mbox      = mbox;
+  proc_thread_self  = thread;
+
   scheme_master_proc_thread = mz_proc_thread_create(master_scheme_place, NULL);
 }
+#endif
 
 /*========================================================================*/
 /*                       precise GC traversers                            */
diff --git a/src/mzscheme/src/schpriv.h b/src/mzscheme/src/schpriv.h
index 72e306400b..522b33a254 100644
--- a/src/mzscheme/src/schpriv.h
+++ b/src/mzscheme/src/schpriv.h
@@ -356,6 +356,9 @@ extern THREAD_LOCAL Scheme_Thread *scheme_first_thread;
 #define scheme_jumping_to_continuation (scheme_current_thread->cjs.jumping_to_continuation)
 #define scheme_multiple_count (scheme_current_thread->ku.multiple.count)
 #define scheme_multiple_array (scheme_current_thread->ku.multiple.array)
+#include "mzrt.h"
+extern mz_proc_thread *scheme_master_proc_thread;
+extern THREAD_LOCAL mz_proc_thread *proc_thread_self;
 #endif
 
 typedef struct Scheme_Thread_Set {
@@ -2687,6 +2690,7 @@ Scheme_Object *scheme_modidx_shift(Scheme_Object *modidx,
 				   Scheme_Object *shift_to_modidx);
 
 Scheme_Object *scheme_intern_resolved_module_path(Scheme_Object *o);
+Scheme_Object *scheme_intern_resolved_module_path_worker(Scheme_Object *o);
 
 Scheme_Object *scheme_hash_module_variable(Scheme_Env *env, Scheme_Object *modidx, 
 					   Scheme_Object *stxsym, Scheme_Object *insp,
@@ -3121,7 +3125,7 @@ typedef struct Scheme_Place {
 } Scheme_Place;
 
 Scheme_Env *scheme_place_instance_init();
-
+void spawn_master_scheme_place();
 
 /*========================================================================*/
 /*                           engine                                       */