I'm trying to use the new autocomplete plugin (1.8rc2).  But, I think this is really a json/ajax issue.  I'm essentially copying the autocomplete demo remote-with-cache.html.  When I enter the text in the autocomplete box I've watched with wireshark and I see the query go out to my server and the reply (with a 200 completion).  If I open the net panel in FB, it also shows the reply coming back with a 200 completion.  I can click on the headers tab in FB and see the headers fine.  However, if I click on the response tab, it is empty.  Also where the net tab (in Firebug) shows the size of the return, there's a "?".  If I type the URL directly into a browser, then the display shows the json data fine (which looks like '["suggestion1", "suggestion2", "suggestion3"]' without the single quotes).  The http header analysis shows the data is coming backed chunked and that may explain the "?", but the ajax code returns null as the response (console.log(response) displays null).  Unfortunately, this is my first ajax/json code and I'm not sure if the problem is in something I'm doing (or not doing) in the ajax code or whether it's something funky in what the server is generating that is confusing the ajax code.  Anyone have any ideas where I should look next?