((GridBoundColumn) e.Column).Aggregate = GridAggregateFunction.Sum problem

[arijit]

I have a RadGrid (2012 Q1) with two levels and autogenerated columns.
In Column Created event I have
((GridBoundColumn) e.Column).Aggregate = GridAggregateFunction.Sum;

When I am expanding second level it is working for the first time, second time i am getting

Object reference not set to an instance of an object.
[NullReferenceException: Object reference not set to an instance of an object.]
   Telerik.Web.UI.GridBoundColumn.ApplyAggregates35(TableCell cell, String footerText) +132
   Telerik.Web.UI.GridBoundColumn.cell_DataBinding(Object sender, EventArgs e) +492
   System.Web.UI.Control.OnDataBinding(EventArgs e) +99
   System.Web.UI.Control.DataBind(Boolean raiseOnDataBinding) +92
   System.Web.UI.Control.DataBind() +15
   System.Web.UI.Control.DataBindChildren() +211
   System.Web.UI.Control.DataBind(Boolean raiseOnDataBinding) +102
   System.Web.UI.Control.DataBind() +15
   Telerik.Web.UI.GridItem.SetupItem(Boolean dataBind, Object dataItem, GridColumn[] columns, ControlCollection rows) +517
   Telerik.Web.UI.GridTableView.CreateFooterItem(Boolean useDataSource, GridColumn[] copiedColumnSet, GridTFoot tfoot) +92
   Telerik.Web.UI.GridTableView.CreateControlHierarchy(Boolean useDataSource) +1009
   Telerik.Web.UI.GridTableView.CreateChildControls(IEnumerable dataSource, Boolean useDataSource) +549
   System.Web.UI.WebControls.CompositeDataBoundControl.PerformDataBinding(IEnumerable data) +57
   System.Web.UI.WebControls.DataBoundControl.OnDataSourceViewSelectCallback(IEnumerable data) +114
   System.Web.UI.DataSourceView.Select(DataSourceSelectArguments arguments, DataSourceViewSelectCallback callback) +31
   System.Web.UI.WebControls.DataBoundControl.PerformSelect() +142
   Telerik.Web.UI.GridTableView.PerformSelect() +16
   System.Web.UI.WebControls.BaseDataBoundControl.DataBind() +73
   Telerik.Web.UI.GridTableView.DataBind() +233
   Telerik.Web.UI.GridDataItem.OnExpand() +289
   Telerik.Web.UI.GridItem.set_Expanded(Boolean value) +109
   Telerik.Web.UI.GridExpandCommandEventArgs.ExecuteCommand(Object source) +34
   Telerik.Web.UI.RadGrid.OnBubbleEvent(Object source, EventArgs e) +134
   System.Web.UI.Control.RaiseBubbleEvent(Object source, EventArgs args) +37
   Telerik.Web.UI.GridItem.OnBubbleEvent(Object source, EventArgs e) +87
   System.Web.UI.Control.RaiseBubbleEvent(Object source, EventArgs args) +37
   System.Web.UI.WebControls.Button.OnCommand(CommandEventArgs e) +118
   System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) +166
   System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +10
   System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +13
   System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +36
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1565

Can anyone please help? or its a permanent bug ?

Regards
Arijit

[Eyup]

Hi Arijit,

This bug will be fixed for the future releases.

Sorry for any inconvenience caused.

All the best,
Eyup
the Telerik team