If you run into an HTML_AJAX problem only on some servers, chances are your running into a
problem with output compression. If the output compression is handled in the PHP config we detect
that and do the right thing, but if its done from an apache extension we have no way of knowing its
going to compress the body. Some times setting HTML_AJAX::sendContentLength to false fixes the
problem, but in other cases you'll need to disabled the extension for the AJAX pages.
I've also seen problems caused by debugging extensions like XDebug, disabling the extension on the
server page usually fixes that. Questions dealing with Using HTML_AJAX, and general JavaScript
development