Detected an attempt to call a symbol in …

“Detected an attempt to call a symbol in system libraries that is not present on the iPhone”
在尝试复制《IPhone Game Development》的例子时遇到了这个错误，似乎应该是Simulator 4.1对SDK 4.1的支持有问题。把Simulator的版本换作4.0.1就行了。