diff --git a/C/init.c b/C/init.c
index c385c0341..2d878dda4 100755
--- a/C/init.c
+++ b/C/init.c
@@ -1155,6 +1155,14 @@ Yap_InitThread(int new_id)
     if (!(new_s = (struct worker_local *)calloc(sizeof(struct worker_local), 1)))
       return FALSE;
     Yap_local[new_id] = new_s;
+    if (!((REGSTORE *)pthread_getspecific(Yap_yaamregs_key))) {
+      REGSTORE *rs = (REGSTORE *)calloc(sizeof(REGSTORE),1);
+      pthread_setspecific(Yap_yaamregs_key, (const void *)rs);
+      REMOTE_ThreadHandle(new_id).default_yaam_regs = rs;
+      REMOTE_ThreadHandle(new_id).current_yaam_regs = REMOTE_ThreadHandle(new_id).default_yaam_regs;
+      rs->worker_id_ = new_id;
+      rs->worker_local_ = REMOTE(new_id);
+    }
   }
   InitWorker(new_id);
   return TRUE;
diff --git a/C/threads.c b/C/threads.c
index 29c866060..df5af91cb 100755
--- a/C/threads.c
+++ b/C/threads.c
@@ -94,15 +94,24 @@ store_specs(int new_worker_id, UInt ssize, UInt tsize, UInt sysize, Term *tpgoal
   REMOTE_ThreadHandle(new_worker_id).ssize = ssize;
   REMOTE_ThreadHandle(new_worker_id).tsize = tsize;
   REMOTE_ThreadHandle(new_worker_id).sysize = sysize;
-  REMOTE_c_input_stream(new_worker_id) = LOCAL_c_input_stream;
-  REMOTE_c_output_stream(new_worker_id) = LOCAL_c_output_stream;
-  REMOTE_c_error_stream(new_worker_id) = LOCAL_c_error_stream;
+
+  if ((REGSTORE *)pthread_getspecific(Yap_yaamregs_key)) {
+    REMOTE_c_input_stream(new_worker_id) = LOCAL_c_input_stream;
+    REMOTE_c_output_stream(new_worker_id) = LOCAL_c_output_stream;
+    REMOTE_c_error_stream(new_worker_id) = LOCAL_c_error_stream;
+  } else {
+    // thread is created by a thread that has never run Prolog
+    REMOTE_c_input_stream(new_worker_id) = REMOTE_c_input_stream(0);
+    REMOTE_c_output_stream(new_worker_id) = REMOTE_c_output_stream(0);
+    REMOTE_c_error_stream(new_worker_id) = REMOTE_c_error_stream(0);
+  }
   pm = (ssize + tsize)*1024;
   if (!(REMOTE_ThreadHandle(new_worker_id).stack_address = malloc(pm))) {
     return FALSE;
   }
   REMOTE_ThreadHandle(new_worker_id).tgoal =
-    Yap_StoreTermInDB(Deref(*tpgoal),7);
+    Yap_StoreTermInDB(Deref(*tpgoal), 7);
+        
   REMOTE_ThreadHandle(new_worker_id).cmod =
     CurrentModule;
   tdetach = Deref(*tpdetach);