RequiredFieldValidator not Working with RadComboBox

[Tim]

I am using Version=2011.2.712.35 and am having a problem getting the RadComboBox to work properly with the RequiredFieldValidator. I have verified that the RequiredFieldValidator works with a DropDownList and then replaced the ddl with the rcb and it works no longer

<telerik:RadComboBox ID="ddlSourceSystem" runat="server" Width="250px" Height="220px" AllowCustomText="True"
         ShowToggleImage="True" CausesValidation="false" ShowMoreResultsBox="false" EnableLoadOnDemand="false"
         MarkFirstMatch="false" EnableVirtualScrolling="false" AutoPostBack="false">
         <CollapseAnimation Type="OutQuint" Duration="200"></CollapseAnimation>
     </telerik:RadComboBox>

<asp:RequiredFieldValidator runat="server" ID="rfvSourceSystem" ValidationGroup="accountValidation"
                ControlToValidate="ddlSourceSystem" ErrorMessage="Source System is required"
                InitialValue="" Text=""><img src="images/exclamation_red.png" width="16" height="16"/></asp:RequiredFieldValidator>

[Tim]

Never mind I don't know what happened but I ran it in a different project and it works.