dyld:未找到符号:_NSURLSessionTransferSizeUnknown AFNetworking 2.1.0

我用Cocoa pod安装了最新的2.1.0版AFNetworking.当我在6.1模拟器上运行应用程序时,我收到以下错误:

dyld: Symbol not found: _NSURLSessionTransferSizeUnknown
  Referenced from: /Users/OskarLarsson/Library/Application Support/iPhone Simulator/6.1/Applications/7F665584-0657-4E3E-A416-87C018E6964C/xxxx.app/xxxxx
  Expected in: /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator6.1.sdk/System/Library/Frameworks/Foundation.framework/Foundation
 in /Users/OskarLarsson/Library/Application Support/iPhone Simulator/6.1/Applications/7F665584-0657-4E3E-A416-87C018E6964C/xxxx.app/xxxx
(lldb) 

我在Mac OS X 10.8上发现了一个类似的问题AFNetworking 2.0"_NSURLSessionTransferSizeUnknown"链接错误,但是由于我的应用程序仍然在此版本的AFNetworking和iOS 6.1上崩溃,我想知道是否有人知道我做错了什么或是否我忘记了什么.

我正在使用:AFNetworking 2.1.0,Mac OS X 10.9.1和Xcode 5