Hello Juan Nin,
JN> just a comment.. Debian kannel packages are outdated... I saw... I sent a "wish" via reportbug to the mantainer and eventually I'll install v.1.4.0 from http://www.litux.org/debian. Anyway I finally succedeed! The config was OK, it was a really stupid matter, sorry if I bothered you all: in /etc/default/kannel there was a "#START_SMSBOX=1"... Cheers, Matteo