iOS semantic build issue (CV_CAP_IOS undeclared)

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Dear All,
I am learning face detection from the following link: http://code.opencv.org/svn/gsoc2012/ios/trunk/shared/ . When I build the project, CvCaptureController.mm has a symbol named CV_CAP_IOS and compiler can't find. The error is "Use of undeclared identifier CV_CAP_IOS". I can't find the symbol anywhere.

How can I solve the problem?