diff --git a/ChangeLog b/ChangeLog
index b07253f66..d7de7ff43 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2002-10-10  Miguel de Icaza  <miguel@ximian.com>
+
+	* gtk/ThreadNotify.cs: Avoid multiple notifications.
+
 2002-10-09  Miguel de Icaza  <miguel@ximian.com>
 
 	* glue/adjustment.c (gtksharp_gtk_adjustment_get_page_size): Added
diff --git a/gtk/ThreadNotify.cs b/gtk/ThreadNotify.cs
index 3301829e6..afae2fdf7 100644
--- a/gtk/ThreadNotify.cs
+++ b/gtk/ThreadNotify.cs
@@ -68,12 +68,17 @@ namespace Gtk {
 			byte s;
 			
 			unsafe {
-				read (pipes [0], &s, 1);
+				lock (this) {
+					read (pipes [0], &s, 1);
+					notified = false;
+				}
 			}
 			
 			re ();
 		}
 
+		bool notified = false;
+		
 		/// <summary>
 		///   Invoke this function from a thread to call the `ReadyEvent'
 		///   delegate provided in the constructor on the Main Gtk thread
@@ -82,7 +87,13 @@ namespace Gtk {
 		{
 			unsafe {
 				byte s;
-				write (pipes [1], &s, 1);
+
+				lock (this){
+					if (notified)
+						return;
+					write (pipes [1], &s, 1);
+					notified = true;
+				}
 			}
 		}
 	}