I defined a ItemFileWriteStore named 'store' in dojo 1.1. And set a new value into the store. But it can't update the new data into the json file.

dojoType="dojo.data.ItemFileWriteStore" jsId="store" url="/json/treeTest.json"
......
store.save();

It not prompt any error, but the data in treeTtest.json isn't changed.