IE9 - c00c023f Error

[Peter Farrell]

On IE9 and Prototype 1.7, we're occasionally see this exception similar to this (the message is always the same):

UserAgent: 'Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; WOW64; Trident/5.0)'
JSException: 'Could not complete the operation due to error c00c023f.'
JSUrl: 'https://XXXXXX/js/prototype.js?1310954924'
Timestamp: '{ts '2011-09-10 17:02:25'}'

Our Prototype file is compressed using JSMin, but we've seen the same issue with uncompressed versions.  It appears that it's not just a Prototype issue since WebSync had a similar issue in their product -- here's the redux:

> It turns out this only happens if you've got the standards and IE9 rendering modes both set (hence my inability to reproduce it at first - thank goodness for the dev tools in IE now), and you've got all script errors on, so the good news is that this won't be a problem for 99% of your users (unless they're running with script debugging on, which is *not* the default in IE9).

> For those who are interested in what the problem was: it shows up because an aborted request comes through with a readyState of "4", which is the same state as "successful", and we were processing it as such (intentionally - we check later for successful completion). However, in IE9, when you abort during an unload, the status, etc, doesn't get set properly, and when you try and read it an exception is thrown. We're now flagging requests in the unload event before they're aborted and ignoring them.

https://groups.google.com/forum/#!topic/websync/ysBEvtvMyb0

So it appears that Prototype isn't handling readyState "4" properly if the request is aborted.

Another reference is here:

http://stackoverflow.com/questions/7287706/ie-9-javascript-error-c00c023f

Are others seeing this issue...?? And what needs to be done to get this fixed?