window.dhtmlHistory.create({ 
        toJSON: function(o) {
                return JSON.stringify(o);
        }
        , fromJSON: function(s) {
                return JSON.parse(s);
        }
}); 

var yourListener = function(newLocation, historyData) {
        if (newLocation){
				regresaMenu(newLocation);
				cambia(this);
			} else {
				regresaMenu("inicio.php");
			}
}

window.onload = function() {
        dhtmlHistory.initialize();
        dhtmlHistory.addListener(yourListener);
};