diff --git a/xpcom/threads/plevent.c b/xpcom/threads/plevent.c
index 94169042f738..b63687962a69 100644
--- a/xpcom/threads/plevent.c
+++ b/xpcom/threads/plevent.c
@@ -497,6 +497,8 @@ PL_ProcessPendingEvents(PLEventQueue* self)
     PR_EnterMonitor(self->monitor);
     
     if (self->processingEvents) {
+      _pl_AcknowledgeNativeNotify(self);
+      self->notified = PR_FALSE;
       PR_ExitMonitor(self->monitor);
       return;
     }