5745deb8 introduced linking with dl libraries, but it was not added to the .pc files. Therefore list of link flags given by pkg-config is incomplete and fails if `-ldl` is not added manually.

I have attached a patch which uses CMAKE_DL_LIBS variable (http://www.cmake.org/cmake/help/cmake2.6docs.html#variable:CMAKE_DL_LIBS)

Thanks,

Isuru Fernando