similar problem is discussed here:
http://www.ericmmartin.com/projects/simplemodal/#comment-6175

adding <meta http-equiv="X-UA-Compatible" content="IE=EmulateIE7" /> fixed the problem

But best would be to find reason and fix it also for standard IE8 mode

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To John for further triage. Is this a general "we don't grok ie8 yet" bug, and if so
is there an umbrella bug for such? If not, could you just mark this as accepted?

I don't like IE8 too (as all IE), but I think is time to not ignore IE8, because if
it will be released officially, it will be late to fix such bugs. 
50% of users of our applications have IE :-(

Occurs with GWT 1.6.2 too. Using -style DETAILED the javascript function containing
style.setExpression() is

function
com_google_gwt_user_client_ui_impl_PopupImplIE6_$onShow__Lcom_google_gwt_user_client_ui_impl_PopupImplIE6_2Lcom_google_gwt_user_client_Element_2(popup)

I commented out the style.setExpression() lines in the onShow() generated javascript
and my popup windows seemed to work just fine in IE8 and IE6:

function
com_google_gwt_user_client_ui_impl_PopupImplIE6_$onShow__Lcom_google_gwt_user_client_ui_impl_PopupImplIE6_2Lcom_google_gwt_user_client_Element_2(popup){
  var frame = $doc.createElement($intern_1350);
  frame.src = $intern_1351;
  frame.scrolling = $intern_1352;
  frame.frameBorder = 0;
  popup.__frame = frame;
  frame.__popup = popup;
  var style = frame.style;
  style.position = $intern_1314;
  style.filter = $intern_1353;
  style.visibility = popup.style.visibility;
  style.border = 0;
  style.padding = 0;
  style.margin = 0;
  style.left = popup.offsetLeft;
  style.top = popup.offsetTop;
  style.width = popup.offsetWidth;
  style.height = popup.offsetHeight;
  style.zIndex = popup.style.zIndex;
/*
  style.setExpression($intern_110, $intern_1354);
  style.setExpression($intern_111, $intern_1355);
  style.setExpression($intern_91, $intern_1356);
  style.setExpression($intern_93, $intern_1357);
  style.setExpression($intern_1358, $intern_1359);
*/
  popup.parentElement.insertBefore(frame, popup);
}

This is GWT 1.5.3.

I've been working on explicit IE8 support (see  issue 3558 ), which should make this
problem go away.

This is fixed along with  issue 3558  (IE8 now completely skips all that stuff).

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I still get erroneous behavior in IE8. However, if I put it in IE7 compatible mode, 
it works fine. 

I upgraded to GWT 1.7 (from 1.6) and it didn't seem to fix the issue. I still get :
Webpage error details

User Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; .NET CLR 
1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; MS-RTC LM 
8; InfoPath.2)
Timestamp: Mon, 3 Aug 2009 17:02:15 UTC


Message: Not implemented

Line: 1867
Char: 324
Code: 0
URI: 
http://localhost:8080/MyProject/myproject/71C57EA2A332BD00DED9E2B73394450A.cache.html

If you could post a sample that exhibits this behavior, that would be really helpful.
The PopupImpl code that was using expressions is definitely not called on IE8 under
normal circumstances.

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