Kevin, Follow your instructions, I have passed my build. A couple of follow-up questions: 1. Why we use the 8A428 instead of 8C46. What they really mean? Where we can find out the descriptions for such numbers? 2. If I want to build a keychain app by using these header files and libraries in my real OS X environment, what results such as those files in the BuildRoot directory I should move into the directory /usr/local or somewhere in the system? Thanks a lot, Ben