Cannot find <opencv2/opencv.hpp> under XCode 4.4 OS10.8
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I just updated my Mac OS to Mountain Lion, and also the XCode to version 4.4.

However after updating I can no longer build any of my codes. XCode keeps complaining that
 
    Lexical or Preprocessor Issue
    opencv2/opencv.hpp file not found

For every single #include <opencv2/opencv.hpp> It was working perfectly okay the day before. It also complains the same issue for #include <boost/foreach.hpp>. 

FYI: I had my boost and opencv libraries installed thru Homebrew.

Does anyone else have the same issue, or does anyone have any idea how to resolve these issues ?

Thanks in advance.