code: function(newParams) {
          var upperParams = OpenLayers.Util.upperCaseObject(newParams);
          var newArguments = [upperParams];
          return OpenLayers.Layer.Grid.prototype.mergeNewParams.apply(this, 
                                                               newArguments);
      }
docs: APIMethod: mergeNewParams
  Catch changeParams and uppercase the new params to be merged in
  before calling changeParams on the super class.
  
  Once params have been changed, the tiles will be reloaded with
  the new parameters.
  
  Parameters:
  newParams - {Object} Hashtable of new params to use