MXHR mode unable to function in IE <= 8

[revmischa]

IE MXHR object does not allow reading the response until the request is closed. Stream.js throws an exception on IE (<= 8 I believe) with MXHR.

Stream.js claims that it validates appropriate MXHR objects that support reading the response body before the request is complete, but I am unable to make it work without throwing an exception on IE8.

To reproduce: try using Hippie on IE8 with script debugging enabled.