RadComboBox.SelectedItem is null

[TravelMan]

We populated radComboBox in page_load method once it not from post back. When the user click a button and we will read selected item using following code

cmbCustAcctNo.SelectedItem.Text

However, we got object null reference because SelectedItem is null. We have verified EnableLoadOnDemand = false and AllowCustomText = false. Do we miss anything? 

version: 2008.2.826.35

<telerik:RadComboBox ID="cmbCustAcctNo" Width="128px"
    runat="server" Skin="Office2007" CausesValidation="false" AutoPostBack="true"
    ToolTip="Select Account Number"
    onselectedindexchanged="cmbCustAcctNo_SelectedIndexChanged">
</telerik:RadComboBox>

IList<prcWebAccountsForUserResult> listOfAcctNo = accountNumbers.ToList();
cmbCustAcctNo.DataSource = listOfAcctNo;
cmbCustAcctNo.DataTextField = "AccountNumber";
cmbCustAcctNo.DataValueField = "AccountNumber";
cmbCustAcctNo.DataBind();

[Helen]

Hello,

We tested the behavior locally, but couldn't reproduce the issue. Please find attached our test files.
Do the attached page work at your side?
If yes - could you please modify it so we can see the problem locally?

Greetings,
Helen
the Telerik team