What I do is actually even better, and you can use it with any proxy program or server available. Mabinogi checks a client's identity only in a certain phase, the login phase. Once you've logged in, it assumes that the identity has been checked already, and it should be fine. Normally it should be, because if you change IP, the connection is no longer valid and you have to login again...
But there's one flaw. When you go to the character selection screen, detection is halted. You are not in any certain realm anymore, so for a moment there's no actual connection. This is the moment to close the proxy server, and start connecting with your own IP. Since the game is already started, it will not check to see if you're a foreighner, and since you're switching from one server to another, there's no actual connection for a brief moment, so no connection can fail either.
And there you are, connecting with Mabinogi with your own IP, the most direct connection you will have.