Maintain scroll position on postback does not work when files are deployed to remote server

[Keithb]

The maintain scroll position on postback feature works as expected with my
site running under localhost on the development machine. When the files are
posted to an IIS 6.0 web server running on a Win2k3 box, maintain scroll
position on postback simply does not work.

The Page_Load event handler in my aspx page has:

Page.MaintainScrollPositionOnPostBack = true;
The Page_Load event handler in the UserControl has:

Page.SetFocus(Grid);
Page.MaintainScrollPositionOnPostBack = true;

The web.config file has:

<pages theme="BTMDefault" maintainScrollPositionOnPostBack="true"
smartNavigation="false"/>

What could be the cause of this problem?

Thanks,

Keith