diff --git a/checkin_notes b/checkin_notes
index 24ae8266c4..b5bfd0f971 100644
--- a/checkin_notes
+++ b/checkin_notes
@@ -7091,3 +7091,11 @@ David  5 Oct 2010
 
     client/
         cs_prefs.cpp
+
+Charlie 6 Oct 2010
+    - ss_app: call rpc.init(NULL) not rpc.init("localhost") to work around 
+        a bug which prevented default screensaver boincscr from communicating 
+        with client on Mac (and probably other computers which support IPV6.)
+
+    clientscr/
+        ss_app.cpp
diff --git a/clientscr/ss_app.cpp b/clientscr/ss_app.cpp
index 5ac8484a40..7440a4184c 100644
--- a/clientscr/ss_app.cpp
+++ b/clientscr/ss_app.cpp
@@ -374,7 +374,7 @@ void app_graphics_render(int xs, int ys, double t) {
 
     if (!connected) {
         if (t > next_connect_time) {
-            retval = rpc.init("localhost");
+            retval = rpc.init(NULL);
             if (!retval) {
                 retval = update_data();
             }
@@ -481,7 +481,7 @@ int main(int argc, char** argv) {
 #endif
 
     if (test) {
-        retval = rpc.init("localhost");
+        retval = rpc.init(NULL);
         if (!retval) {
             retval = update_data();
         }