AFAIK, iptables will not perform logging about rule matches unless you explicitly tell it to, a la:
Code:
# Log / allow in ssh
/sbin/iptables -A INPUT -p tcp -m state --state NEW -m tcp --dport 22 -j LOG
/sbin/iptables -A INPUT -p tcp -m state --state NEW -m tcp --dport 22 -j ACCEPT
See the manpages for iptables(8) -- the LOG section in particular.