> Where is the syslog daemon started?

In /etc/rc.conf, set syslogd=YES for it to start automatically on boot.

> And where can i add the option -s when i starts?

In /etc/rc.conf, set syslogd_flags="-s"

> Can ppl do nasty things with port 514, syslogd open?

Who knows?

Of course just typing syslogd -s at a root prompt would do..

Cheers,

Patrick