Thanks to all of you for your answers.
ppr:kut, I took a look at your files.
Unfortunately common-daemons doesn't build:
./commons-daemon.SlackBuild: line 55: ant: command not found
though I built and installed apache-ant first.
<edit>ant executable was not in my path because it's installed in /opt (I should have checked that at first), I made a symlink to it, then I could build && install commons-daemon and start tomcat using rc.apache-tomcat.</edit>
I'll give you more details in a private message. Anyway we are not in a hurry as submissions to slackbuilds.org are frozen till 12.2 release