Modal Popup Disable Background

I have a modalpopup for viewing some labels and buttons. But when i show modalpopup, background will not be disabled in IE 7 (it works for Firefox 2.0.0.3) . I looked at the codes in

( http://ajax.asp.net/ajaxtoolkit/ModalPopup/ModalPopup.aspx ), but it has <atlas tags, not <asp tags.

Any idea?

Regards..

if you use the default css classes which are also used in the ajaxcontroltoolkit samplewebsite the background will be disabled in FF, IE6 and IE7.

Of course i tried it before writing here. But it did not work.

Regards..