ScriptManager in UserControl

I added a Script Manager in a user control and got the following error message: “Only one instance of a ScriptManager can be added to the page.”
The issue is the parent page (either the aspx page or master page) has a scriptmanager.
Now comes another part I added the UpdatePanel but I found out that when I wanted a partial refresh Page_Load event is getting fired!!
This could be b’coz the way this Control is called in the aspx page!!
Even if you do AJAX if the aspx calls the control in page load event we will not be able to help it out.
Bottomline: Think twice before adding AJAX in usercontrol.