Save changes button doesn't call update method (apply changes from template column)

[Yuriy]

Hi

I have grid with template for column A

template: '<input type="checkbox" class="Acolumn" #= A ? checked="checked" : "" # />'

and delegate 

$(divGrid).delegate(".AColumn", "click", function (e) {

                var dataItem = grid.dataItem($(this).closest("tr"));

                dataItem.A = $(this).is(':checked');

            });

Data Source configured with following options: autosync, transport update url, batch

Grid configuration : editable. Save changes button at the grid header.

It works ok when checkbox is selected data in data source changed successfully but Save changes button of the grid doesn't call update method of data source. 

What could be a reason of this issue?