Whenever I try to access event.data, event.origin, ect. when using IE8 beta 2 from a message event, it says "Error: 'data' is null or not an object". msdn says that IE 8 beta 2 supports the standard HTML5 message events and I remember some time ago I was able to make IE alert the message event data.
PHP Code:
function handleMessage(e) {
alert(e.data);
}
window.onmessage = handleMessage;
window.postMessage('TEST','*');
Also
uploaded here so you can test it out yourself.
This is the ONLY thing stopping me from adding support for IE8 beta 2 to my jData host script.
Edit: This is the msdn page:
http://msdn.microsoft.com/en-us/libr...15(VS.85).aspx
Update: I just noticed it works when I use attachEvent for some reason.
Before you post, read our: 
