The onFailure function provided to Tapestry.ajaxRequest does not always get invoked

Even if i create my own exceptionhandler function and register it through the Tapestry.ajaxRequest(url,

) the exception handled is not called when an exception is thrown.I think the problem is in the succes function that tapestry.js overwrites we have this snippet of code when the status is 0 or the request was not a success

if (!response.getStatus() || !response.request.success()) {
Tapestry.error(Tapestry.Messages.ajaxRequestUnsuccessful);
return;
}

it returns before calling the exception handler