I would like to propose the idea of having an ingame messenger, maybe not exact replica as that may be pretty hard to do, but something comparable.
Here are the patch notes:
UO Live Access Patch (Aug. 26) Nov 16 1999 5:01PM CST
Ultima Messenger FAQ
How do I access my messages?
* Open your paperdoll. Double left-click the Messenger Bag located at the top of your Paperdoll. This will bring up the Ultima Messenger.
How do I give someone my address?
* Open your paperdoll. Drag the Messenger Bag from the top of your Paperdoll on to the person you wish to exchange mail with. This will send them a greeting card and add you to their address book. Remember, they must do the same to you if you want to send them a message.
How do I stop someone from sending messages to me?
* There are two ways to stop someone from messaging you. Either highlight a message the person has sent you or open up your address book and highlight that person's address. Then click the "Revoke Address" button at the bottom of the Ultima Messenger window (an icon with a Person and an "X").
http://web.archive.org/web/200003032043 ... gn_25.html