adjust the follow ports to be subnet specific for samba stuff 

-A RH-Firewall-1-INPUT -p udp -m udp -s 192.168.0.0/24 --dport 137 -j ACCEPT
-A RH-Firewall-1-INPUT -p udp -m udp -s 192.168.0.0/24 --dport 138 -j ACCEPT
-A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp -s 192.168.0.0/24 --dport 139 -j ACCEPT
-A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp -s 192.168.0.0/24 --dport 445 -j ACCEPT