Well yes and no. You need to be more specific about what your NAT is. Are you talking about a Joe-Standard Linksys/Netgear router?
If so, a simple port forward will fix part of your problem. Port forwarding all the EQEmu ports to the local IP of the machine you are hosing your EQEmu server on will work like a champ.
The issue will still remain, if you are using minilogin that is, that only one person per IP will be able to play. So if two of your friends are on their own PC's behind the same router, then only one of them will be able to connect... this is because that as far as the rest of the world is concerned (your EQEmu server included) their Router's IP is all that is visible.
My solution was to go with a VPN. I chose Hamachi (
http://www.hamachi.cc/download/list.php) and its worked great. There is a 16 person per network limit on the free version though, so depending on your expected server load, it may not work for you. I purchased it, so I can host upto 256 peeps.
Additionally, I wrote a simple client/server app that is used to perform EQEmu account authentication when using minilogin. I added a single column to the accounts tab that stores an additional password. What the MyClient software does is make the user put in their account username, password and Hamachi IP and then contacts MyServer app. The MyServer app then hits the Accounts table in my PEQ data base, looks up the account and checks the supplied Password to the new password column. If it authenticates properly, then the MyServer app sets that account's Minilogin IP to the supplied Hamachi IP address. Then the client can launch their EQ and successfully connect to my server.
MyServer pings each MyClient once every 10 seconds to check connection status, if ping fails then the MyServer hits the account table again and sets that account's Minilogin IP to something impossible (0.0.0.0) to lock out that account so that no one else can use it without the AccountName and Password
...just some ideas of what is possible for ya.