The documentation howto
is almost right, but (x)inetd needs to be configured, even if my version is > 10.04

I found that inetd was installed as default but the file/etc/inetd.conf was missing and I've needed to create it and put in it the line:
saned stream tcp nowait root /usr/sbin/saned saned
(where to know the path of your saned you can just use "which saned" in a terminal window, in case it is not /usr/sbin/saned).