我正在试用 AFNetworking 的新版本 2.0，但出现上述错误。知道为什么会这样吗？这是我的代码：

    NSURL *URL = [NSURL URLWithString:kJSONlink];
    NSURLRequest *request = [NSURLRequest requestWithURL:URL];
    AFHTTPRequestOperation *op = [[AFHTTPRequestOperation alloc] initWithRequest:request];
    op.responseSerializer = [AFJSONResponseSerializer serializer];
    [op setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
        NSLog(@"JSON: %@", responseObject);
    } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
        NSLog(@"Error: %@", error);
    }];
    [[NSOperationQueue mainQueue] addOperation:op];

我正在使用 Xcode 5.0。

另外，这是错误消息：

Error: Error Domain=AFNetworkingErrorDomain Code=-1016 "Request failed: unacceptable content-type: text/html" UserInfo=0xda2e670 {NSErrorFailingURLKey=kJSONlink, AFNetworkingOperationFailingURLResponseErrorKey=<NSHTTPURLResponse: 0xda35180> { URL: kJSONlink } { status code: 200, headers {
    Connection = "Keep-Alive";
    "Content-Encoding" = gzip;
    "Content-Length" = 2898;
    "Content-Type" = "text/html";
    Date = "Tue, 01 Oct 2013 10:59:45 GMT";
    "Keep-Alive" = "timeout=5, max=100";
    Server = Apache;
    Vary = "Accept-Encoding";
} }, NSLocalizedDescription=Request failed: unacceptable content-type: text/html}

我只是使用 kJSONlink 隐藏了 JSON。这应该返回一个 JSON。