diff --git a/lib/OpenLayers/Control/MouseToolbar.js b/lib/OpenLayers/Control/MouseToolbar.js
index e0afdd527b..e5baeed032 100644
--- a/lib/OpenLayers/Control/MouseToolbar.js
+++ b/lib/OpenLayers/Control/MouseToolbar.js
@@ -96,6 +96,7 @@ OpenLayers.Control.MouseToolbar.prototype =
     * @param {Event} evt
     */
     defaultMouseDown: function (evt) {
+        if (!Event.isLeftClick(evt)) return;
         this.mouseDragStart = evt.xy.copyOf();
         if (evt.shiftKey && this.mode !="zoombox") {
             this.switchModeTo("zoombox");
@@ -226,6 +227,7 @@ OpenLayers.Control.MouseToolbar.prototype =
     * @param {Event} evt
     */
     defaultMouseUp: function (evt) {
+        if (!Event.isLeftClick(evt)) return;
         switch (this.mode) {
             case "zoombox":
                 var start = this.map.getLonLatFromViewPortPx( this.mouseDragStart );