Hi Simba,
As you can see from the link you posted http://downloads.sourceforge.net/opencvlibrary/opencv-unix/2.4.3/OpenCV-2.4.3.tar.bz2 Open CV 2.4.3 is not in the fetch directory update link in .bb, why don’t you try upgrading your version to the latest one found on that website, 2.4.10. You can also try building the BSP with a newer source file, you can find it here https://communities.intel.com/docs/DOC-22226.
Regards
Sergio