diff --git a/lib/OpenLayers/Map.js b/lib/OpenLayers/Map.js
index c71e9df1f4..0404bab7b1 100644
--- a/lib/OpenLayers/Map.js
+++ b/lib/OpenLayers/Map.js
@@ -98,6 +98,7 @@ OpenLayers.Map.prototype = {
         this.events.register( "mousedown", this, this.defaultMouseDown );
         this.events.register( "mouseup", this, this.defaultMouseUp );
         this.events.register( "mousemove", this, this.defaultMouseMove );
+        this.events.register( "mouseout", this, this.defaultMouseUp );
 
         // always call map.destroy()
         Event.observe(window, 'unload',