Why ScriptManager in MasterPage is not enough to the toolkitExtender control?

This is the error I get when look on a page and drop the User control that include the ajaxTooltip from any type.

Any suggestion?

Do you use ScriptMangerProxy?you need to use ScriptManager/ ScriptManagerProxy both for master page.

Where to add the ScriptManager and where to add the ScriptManagerProxy to get a clear design time project developing?

To explain the controls, pages, masters I have, here are they:

1. A master page that include a ScriptManager (I try to include a ScriptManagerProxy also).

2. A page that inherit the MasterPage and have a User Control in it by design time(drag and drop).

3. A User Control that have a modalPopupExtender in it, that work properly.

My only problem that other developers use my User Control in them Pages and the User Control(that added to the page) raise a:

Error Rendering Control

An unhandled exception has occurred.

The control with ID 'MpdalPopupExtender1' requires a ScriptManager on the page. The ScriptManager must appear before any controls that need it.

What can I add to the Page, Master or may be web.config?