Adobe iPhone Publisher: URLLoader aborts app on iPad

I am creating an iPad app with Flash CS5. In my app, I am trying to load some dynamic XML from a server. Whenever I click the button to initiate the load, the app immediately aborts and I am taken back to the desktop. Here is my load routine that is run when the button is clicked:

protected function SendRequest():void
{
    var url:String = GetURL();
    var request:URLRequest = new URLRequest(url);

    request.method = URLRequestMethod.POST;
    request.data = GetVariables();

    var loader:URLLoader = new URLLoader();

    try
    {
        loader.load(request);
        ec.add(loader, IOErrorEvent.IO_ERROR, OnIOError, false, 0, true);
        ec.add(loader, Event.COMPLETE, OnRequestComplete, false, 0, true);
    }
    catch (error:Error)
    {
        response_txt.text = error.message;
    }
}

I have tested this app on my desktop computer within开发者_如何转开发 CS5 and it works fine there.

Is it the sandbox security problem? Maybe you need to check the crossdomain.xml file...