Handling Partial and Full Form Resets with radio buttons

Rion W. helped me with with making partial and full form reset buttons. Thanks Rion!
Problem is my partial reset is not working on the radio buttons.
The buttons are;
<asp:RadioButtonList  ID="Limited" TextAlign="Left" runat="server" >
     <asp:Listitem    Text=" Limited " > </asp:Listitem>
      <asp:Listitem  Text="Unlimited "> </asp:Listitem>
</asp:RadioButtonList>
The partial reset uses javascript and looks at id names as follows;
<script type="text/javascript">
    function resetEvent(appForm){
      //Reset event
      appForm.StartDate.value = ''; // OK
      appForm.EndDate.value = ''; // OK
&nb ...