Throwing Exception When Field Is Zero And Clicking Edit Linkbutton

I have a radcombobox in radgrid nested inside FormTemplate:

Code:

<telerik:RadComboBox Skin="WebBlue" Width="250px" Height="150px" runat="server"
ID="TitleCombo" OnDataBound="Title_DataBound"
SelectedValue='<%# Bind("Title") %>' AppendDataBoundItems="true"
OnSelectedIndexChanged="Title_SelectedIndexChanged" AutoPostBack="true" />

then i insert an item to the top of list (at zero index):

Code:

protected void Title_DataBound(object sender, EventArgs e)
{
var item = (RadComboBox)sender;
item.Items.Insert(0, new RadComboBoxItem("Select title...", "0"));
}

It works perfect but, IF the Title field is zero and you Click EDIT LinkButton it throws an exception: Selection out of range Parameter name: value I would say that it's expected as zero index does not exist at the moment when i click edit button. I bind the combo from within RadGrid1_ItemCreated event.