Using cvLoad I get Unspecified error (The node does not represent a user object (unknown type?)) error

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here is the full error message:

OpenCV Error: Unspecified error (The node does not represent a user object (unknown type?)) in cvRead, file /home/abe/Documents/opencv-2.4.6.1/modules/core/src/persistence.cpp, line 4997

I saw on google that this might be a bug here

http://opencv-users.1802565.n2.nabble.com/face-detection-cvLoad-td4467872.html

here is how im running it

#include <cv.h>
#include <highgui.h>
using namespace std;

int main()
{


 cvLoad("/home/abe/Documents/opencv-2.4.6.1/data/haarcascades/haarcascade_frontalface_alt2.xml");

    return 0;
}

many programs load xml files with this function and this file is from opencv directory so i know its good I tried the workaround using cvErode in the above link but still got same error any help is appreciated

btw compile on ubuntu raring with this which works for every other program

g++ b.cpp -o b pkg-config --cflags --libs opencv