Telerik Grid ASP.NET MVC2 missing last column separator

My grid has 5 data columns and 1 command column (update/delete) the column separator between command column and last data column is missing, making everything shift when entering inline edit mode. Any ideas what am I doing wrong ?

this is the grid's view code:

<%= 
                Html.Telerik().Grid<ActivityPOCO>()   
                    .Name("ActivityGrid")
                                    .DataKeys(dataKeys =>
                                    {
                                        dataKeys.Add(e => e.ActivityID);
                                    }
                    .ToolBar(commands => commands.Insert().ButtonType(GridButtonType.Image))
                    .DataBinding(dataBinding => 
                        {
                        dataBinding.Ajax()    //Ajax binding
                .Select("SelectActivityGridAjax", "Activity")
                .Insert("InsertActivityGridAjax", "Activity")
                .Update("UpdateActivityGridAjax", "Activity"
                .Delete("DeleteActivityGridAjax", "Activity");
                        })

                    .Columns(c =>
                        {
                            c.Bound(o => o.ActivityID).Title("ID").ReadOnly(true).Width(30);
                            c.Bound(o => o.ActivityName).Title("NAME").Width(130);
                            c.Bound(o => o.ActivityTimeHours).Title("TIME").Width(50);
                            c.Bound(o => o.Cost).Title("COST").Width(100);
                     开发者_C百科       c.Bound(o => o.WarrentyMonths).Title("WARRENTY");
                            c.Command(commands =>
                                {
                                    commands.Edit().ButtonType(GridButtonType.Image);
                                    commands.Delete().ButtonType(GridButtonType.Image); ;
                                }).Width(180).Title("COMMAND");


                        }).Editable(editing => editing.Mode(GridEditMode.InLine))


            %>

Well, it looks like a problem in the RTL CSS: I've changed the .t-last-header{border-right-width:1;} from 0 and got the separator. Still looking for answer for the grid rows, especially in edit mode...