http://forums.macosxhints.com/showthread.php?t=50342

terminal – sudo touch /etc/rc.local
then…
sudo vi /etc/rc.local and then i to insert…..type..
#!/bin/sh
/sbin/ipfw add 0 deny udp from any to any 2223

to save – hit esc then type :x! and hit enter

then to give it the correct permissions…
sudo chown root:wheel /etc/rc.local
sudo chmod 755 /etc/rc.local

The original Office 2004 info is thanks to Voldenuit.

You can also do the same thing for Office 2004 but use port 2222 instead of 2223.