iOS semantic build issue (CV_CAP_IOS undeclared)

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?