Openinig FileUpload dialog during Page_Load

if (!IsPostBack) { ClientScript.RegisterStartupScript(this.GetType(), "open", "document.getElementById('" + FileUpload1.ClientID + "').click();", true); } I have the above code in my Page_Load event. In IE9, the file upload opens as exected, in FF4, I am warned about popups, and in Chrome, nothing happens at all. Is there a standard way to automatically open the file upload dialog when the page loads?
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