The XmlHttpPanel receives a string containing the HTML that will be pasted within the panel. If this HTML starts with a <script> or <style> tag, these (<script> and <style>) elements will be stripped by the browser and the content will actually start from the first non-<script> (or non-<style>) element. Basically if you have placed your client-script right at the top of the UserControl's markup, the script will never be evaluated because it is not there (it has been removed by the browser). To avoid this behavior you can place the client-script at the bottom of the UserControl, or you can place a hidden <input> just before the <script> tag. For your convenience I have attached a sample project showing how to achieve this. You will notice that everything works fine and the scripts are evaluated.
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