XHR synchronous loading and onreadystatechange

I'm looking for some clarification on the recommended behavior for
synchronous loading. Right now, there is some inconsistency between the
browsers I tested. Firefox 1.5 does not call onreadystatechange handler
after loading a resource synchronously, while both Opera 9.0 and IE 6.0 do.
So, the calling script needs to account for this difference by always
processing the response after send().

>From the archives of this list, I found an open issue
http://www.w3.org/2005/06/tracker/webapi/issues/34, but there does not seem
to be any traction around it.

Subbu