hovermenuextender in datalist image position

Hi, 

   I have a datalist in which i have 2 panels

 and I have Hovermenuextender. hover image is not displaying on the panel

TargetControlID="Panel1"  PopupControlID="Panel2"

here is the HTML 

<asp:DataList ID="dl_Modules" runat="server" RepeatColumns="3" RepeatDirection="Horizontal"

Height="223px" Width="401px" CellSpacing="0">
<ItemTemplate>

<asp:Panel ID="Panel1" runat="server" >
<asp:HyperLink ID="HyperLink1" runat="server"
ImageUrl='<%# Bind("ModImage") %>'
NavigateUrl='<%# Bind("ModURLAdm") %>'>[HyperLink1]</asp:HyperLink>

</asp:Panel>

<asp:Panel ID="Panel2" runat="server">
<asp:HyperLink ID="HyperLink2" runat="server"
ImageUrl='<%# Bind("ModHovImage") %>'
NavigateUrl='<%# Bind("ModURLAdm") %>'>[HyperLink2]</asp:HyperLink>
</asp:Panel>

<cc1:hovermenuextender ID="HoverMenuExtender1" runat="server"
TargetControlID="Panel1" PopupControlID="Panel2" PopupPosition="Center" />

</ItemTemplate>
</asp:DataList>