add: this.buttons = null; this.position = null; 
context:     destroy: function() {        OpenLayers.Control.prototype.destroy.apply(this, arguments);        for(i=0; i<this.buttons.length; i++) {            this.buttons[i].map = null;        }    },
meta: 1027	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/1027/882c71a424a0b1e67afcfce1ca152fb46cfb7587/PanZoom.js/buggy/lib/OpenLayers/Control/PanZoom.js