Then you would most likely be using the web API. What language is the virtual world interface in?
For the web API you just need to include your user application ID from your user page, and your bot's ID. The first web API message will return a conversation ID which you use for other chat messages in the same conversation. So each user you interface with would get a different conversation ID for each conversation.
To record the user's name, just send a message like "My name is Jim" as your first message, then you will have a record of the user's name (a if you have the MyNameIs script the bot will know the user's name, or you can write your own script or response formula for different syntax/response).