Radio button column in a DataGrid

[aroraamit81]

Hi,

I have a RadioButton column in a DataGrid, the problem is it is
allowing me to multi select RadioButtons, where as I dont want to have
post back on Click of radio Button. Here is a code which I am using

<asp:datagrid id="dgNominees" runat="server"
AutoGenerateColumns="False" DataKeyField="AwardNominationID">
<Columns>
<asp:TemplateColumn HeaderText="Select">
<ItemTemplate>
<asp:RadioButton id="rdo"
runat="server"
GroupName=grpNomineesSelection></asp:RadioButton>
</ItemTemplate>
</asp:TemplateColumn>


Any help why this is happening!