如何让cmake找到可选的boost安装?

I have installed the most recent version of boost in /usr/local (with includes in /usr/local/include/boost and libraries in /usr/local/lib/boost) and I am now attempting to install Wt from source, but cmake (version 2.6) can't seem to find the boost installation. It tries to give helpful suggestions about setting BOOST_DIR and Boost_LIBRARYDIR, but I haven't been able to get it to work by tweaking these variables.I have installed the most recent version of boo