I have this:
<asp:UpdatePanel ID="udpPortfolio" UpdateMode="Conditional" runat=server>
<ContentTemplate>
<h2><span>Porfolio</span></h2>
<div class="filter">
<asp:DropDownList ID="ddlFilter" runat="server" AutoPostBack="true" OnSelectedIndexChanged="ddlFilter_OnSelectedIndexChanged"></asp:DropDownList>
</div>
<asp:Repeater ID="rptPortfolio" runat="server" OnItemDataBound="rptPortfolio_OnItemDataBound">
<HeaderTemplate><div id="gallery"><ul class="works"></HeaderTemplate>
<ItemTemplate>
<li>
...
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