There is a problem with the original test case, fileUploadDemo.zip. The failing case fails on IE (& elsewhere) because there's basically a typo in the javascript – the action references "upload.html" instead of "uploadComplete.html". The "fileUploadDemo2.zip" attachment has that fixed.
BTW, the test case also fails on Safari 4 beta for Windows.
On Opera (9.64), there's a twist – the test case works if served up from a webserver, but fails if you just open the page from disk. In the failing case the error console says "Network - file://localhost/C:/TEMP/bugtest/uploadComplete.html The loading of the URL has been blocked for security reasons."
I'm going to add this test case to the bugzilla entry at https://bugzilla.mozilla.org/show_bug.cgi?id=481647, as the Mozilla folks might fix it there.
See issue
ICE-4138for same problem in Safari 4 Beta.