Problem with ListGridField setOptionDataSource

[kapv]

I am trying to use the same datasource in diferent columns, but display different fields.

        DataSource dsitems=new DataSource();
        dsitems.setClientOnly(true);
        ...
        ...
        ListGridField fitem=new ListGridField("Item","Item",150);
        fitem.setOptionDataSource(dsitems);
        fitem.setDisplayField("Name");
        fitem.setValueField("id");

        ListGridField fdesc=new ListGridField("Item","Description",250);
        fdesc.setOptionDataSource(dsitems);
        fdesc.setDisplayField("Description");
        fdesc.setValueField("id");

But unfortunately I see Description in "Item" column and ID in "Description" column. What's wrong in my code?