解决方案：
1.http://blogs.msdn.com/delay/archive/2007/02/05/safely-avoiding-the-access-denied-dialog-how-to-work-around-the-access-denied-cross-domain-iframe-issue-in-the-ajax-control-toolkit.aspx
http://weblogs.asp.net/bleroy/archive/2007/01/31/how-to-work-around-the-quot-access-denied-quot-cross-domain-frame-issue-in-asp-net-ajax-1-0.aspx
2.http://www.cnblogs.com/billchen/archive/2007/07/11/814079.html