-for port in 25 993; do # smtp and imap with ssl.
-e iptables -t mangle $iptables_op OUTPUT -m tcp -p tcp -m multiport --ports $port -j MARK --set-mark 0x1
+for port in 25 143; do # smtp and imap.
+ e iptables -t mangle $iptables_op \
+ OUTPUT -m tcp -p tcp -m multiport --ports $port -j MARK --set-mark 0x1