[LAU] gentoo users help! Jack with freebob

Hello experienced gentoo users! I am in the middle of my first gentoo install and stuck with this problem. I am trying to compile jack with freebob enabled, emerge --search didn't find freebob so I installed it with the classic method configure make make install. Beforehand I had to emerge couple of libs, and everything went fine. Then, following an advice from the irc #gentoo_amd64 I created the directories /etc/portage/env, /etc/portage/env/media-sound, /etc/portage/env/media-sound/jack-audio-connection-kit/ and inside this the file jack-audio-connection-kit in which I put EXTRA_ECONF="--enable-freebob" (I also tried --enable-libfreebob). Afterwards I (re)emerged jack. But no avail, jackd -d freebob says "jackd: unknown driver 'freebob'" I'd appreciate any tips, thanks in advance, Best mea