Why it always return to the original place?

<asp:ScriptManager ID="ScriptManager1" runat="server" />
<cc1:DragPanelExtender ID="DragPanelExtender1" runat="server" TargetControlID="Panel1"
DragHandleID="Panel2">
</cc1:DragPanelExtender>
<asp:Panel ID="Panel1" runat="server" Height="300" Width="200">
<asp:Panel ID="Panel2" runat="server" Height="25" Width="200" BackColor="Black">
</asp:Panel>
Test</asp:Panel>

I would like the Panel1 can be dragged and stay the place where I drop it.

How to do that?

I believe the body of the page has to have been assigned some sort of physical dimension:

http://forums.asp.net/p/1150327/1874846.aspx

See point #23 and Listing 6 of this article:

http://aspalliance.com/1450_Working_with_DragPanel_AJAX_Control.4

Many thanks for replying.