Topic: xajax URI in a reverse-proxied application

Hello, I wonder if anyone has used xajax in a reverse-proxy situation.  Specifically, the protocol (from internet to proxy) starts as HTTPS.  The proxy rewrites the request to a backend server over HTTP.  The xajax request object URI use the HTTP protocol and xajax debug output tells me that the request is SENT and RECEIVED, but then I get this:

ERROR: No response processor is available to process the response from the server.
Content-Type: null

Does anyone know how to handle this situation?  Thank you.