Hi.
To allow samba connections through your firewall you can do this....
iptables -A INPUT -i eth0 -p tcp -m multiport --dport 135,136,137,138,139,445 -j ACCEPT
iptables -A INPUT -i eth0 -p udp -m multiport --dport 135,136,137,138,139,445 -j ACCEPT
What that does in this case is allows samba connections through my eth0 network card.
You will need both lines, the ports there are the ones that samba uses.
Let me know how you go.
Craig