add: req.setRequestHeader('content-type', 'text/x-json+athena') 
context: Nevow.Athena.prepareRemoteAction = function (actionType, args) {    var url = Nevow.Athena.constructActionURL(actionType, args);    var req = MochiKit.Async.getXMLHttpRequest();    try {        req.open('GET', url, true);        yes = 1;    } catch (err) {        return resultD = MochiKit.Async.fail(err);    }    Nevow.Athena.outstandingTransports++;    Nevow.Athena.debug("Setting livepage id " + new String(Nevow.Athena.livepageId));    req.setRequestHeader('Livepage-Id', Nevow.Athena.livepageId);    return resultD = MochiKit.Async.succeed(req);};
meta: 1565	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/1565/6c5638f204c18e9e3c87b0b1d171c3c020212136/athena.js/clean/nevow/athena.js