Tokyo Cabinet (and Kyoto Cabinet, the follow on project) are not in CPAN because the Project Owners (FAL Labs) didn't put them there. Are you volunteering to do the work? The
is documented for you already. All you need to do is package it up and submit it to CPAN. Then comes the hard part -- you have to maintain your package as FAL labs make improvements. It's not that hard, it just takes a little time and interest. It's your itch, you scratch it.