Ehran,
I don't know how accurate this is pertaining to the WoD, but the info from OSI's site on firewalls and ports is :
Question
What are the port numbers I need to play UO behind a firewall or proxy server?
Answer
If you are running Ultima Online behind a firewall or using a proxy server, you will need these port numbers open for incomming and outgoing traffic.
TCP/IP ports:
5001-5010 Game
7775-7777 Login
8888 Patch
8800-8900 UO Messenger
9999 Patch
You will not be able to play UO without access to these open ports.
For information on opening these ports in your firewall or proxy server, please contact either the fire wall/proxy manufacturer or your system administrator.
If these ports can not be opened, you will need to find an alternate method of connecting to the internet where these ports can be opened.
I got this by going to
http://www.uo.com, hitting the 'Support' on the left sidebar menu, then entering 'firewall' in the search term.