add: if (!Event.isLeftClick(evt)) return; 
context:     buttonClick: function(evt) {        this.switchModeTo(evt.div.action);        Event.stop(evt);    },
meta: 1027	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/1027/c92cd6d88a59f79879c73965c26269e13afa25e3/MouseToolbar.js/clean/lib/OpenLayers/Control/MouseToolbar.js