you can try to change the status of selinux to permissive:
Open the file /etc/selinux/config and change the value:
SELINUX=enforcing to SELINUX=permissive
AFAIK, you need to reboot the system for the change to take effect. It will warn you about the things that it would normally block but it'll not block anything. You can change it back if it doesn't help.
When it comes to Iptables (the firewall), as root try to issue
the following command:
iptables -A INPUT -p tcp --dport xxx -j ACCEPT
iptables -A INPUT -p udp --dport xxx -j ACCEPT
(if that doesn't work, try /sbin/iptables -A...........etc)
where xxx is the port number.
and then to save the state of iptables
/sbin/service iptables save
to check the iptables status:
iptables -L
There is a tutorial on iptables (basic configuration is not really difficult)
http://forums.pcper.com/showthread.php?t=432469
hth