$.ajax() will null data property in config object results in missing Content-Length header in FF3

$.ajax() will null data property in config object results in missing Content-Length header in FF3


Just experienced this in Firefox 3, not sure whether it is desired
behavior, but discussed it with a fellow dev and we think it is not.
I had an ajax request as follows:
var myData = null;
$.ajax({
'url' : 'foo.php',
'data' : myData,
'type' : 'POST',
'dataType' : 'json',
'success' : function(j) {
// whatever
}
});
Client was reporting a 411 HTTP response code on the request -- their
proxy was expecting a Content-Length header on the request, and wasn't
getting one. This also occurred if myData was undefined. It did *not*
occur when myData was {}.
We hadn't detected this error internally because our requests weren't
proxy'd. It seems Content-Length "should" always be there
http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.13
and should be 0 if myData is null or undefined.
I'm not sure whether this is just a Firefox issue, or something that
jQuery should address in the spirit of abstracting away browser
differences?