Problem with MultiView and ModalPopupExtender

This one has me completely stumped and has eaten up quite a bit of my time.   I have a MUCH more complex project than you're going to see here but I've been able to reduce it down to the problem itself which you should be able to duplicate.  Let me start with my code:<%@ Page Language="VB" AutoEventWireup="false" ClassName="_Default" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<%@ Register src="UserControls/LoanRequestForm.ascx" tagname="LoanRequestForm" tagprefix="uc" %>

<script runat="server">
Protected Sub btnStepOne_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnStepOne.Click
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