diff --git a/checkin_notes b/checkin_notes
index 064473fa27..17e05053a0 100755
--- a/checkin_notes
+++ b/checkin_notes
@@ -13354,3 +13354,12 @@ Rom    24 Oct 2005
         main.C
     lib/
         diagnostics.C
+
+Charlie 25 Oct 2005
+    - Mac: Work around a bug which caused the core client to block 
+      after receipt of SIGTERM, SIGHUP, SIGINT or SIGQUIT, preventing 
+      the main loop from processing the exit request.
+      
+      client/
+        gui_rpc_server.C
+        
\ No newline at end of file
diff --git a/client/gui_rpc_server.C b/client/gui_rpc_server.C
index 9d74fbab5f..98c787b218 100644
--- a/client/gui_rpc_server.C
+++ b/client/gui_rpc_server.C
@@ -248,6 +248,17 @@ void GUI_RPC_CONN_SET::got_select(FDSET_GROUP& fg) {
     if (FD_ISSET(lsock, &fg.read_fds)) {
         struct sockaddr_in addr;
 
+#ifdef __APPLE__
+    // For unknown reasons, the FD_ISSET() above succeeds on the 
+    // Macintosh after a SIGTERM, SIGHUP, SIGINT or SIGQUIT is 
+    // received, even if there is no data available on the socket.
+    // This causes the accept() call to block, preventing the main 
+    // loop from processing the exit request.  This is a workaround
+    // for that problem.
+    if (gstate.requested_exit)
+        return;
+#endif
+
         boinc_socklen_t addr_len = sizeof(addr);
         sock = accept(lsock, (struct sockaddr*)&addr, &addr_len);