this.map.setCenter(this.map.getLonLatFromPixel(evt.xy), this.map.getZoom() - 1); 
this.wheelChange(evt, -1); 
    wheelDown: function(evt) {        this.map.setCenter(this.map.getLonLatFromPixel(evt.xy),                           this.map.getZoom() - 1);    },
2032	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/2032/f99d1ce7b021ecfe42c60911d940762ac09edfd9/Navigation.js/buggy/lib/OpenLayers/Control/Navigation.js