wp-monalisa is the plugin that smiles at you like monalisa does. place the smilies of your choice in posts, pages or comments.
There is no way to add custom emoticon e.g. "http://www.emoticonsource.com/emoticons/emoticon1.gif", or add an external folder, the script is too hard to modify.
A simple form like this should be useful when somene has to include an emoticon hosted in another server:
Emoticon name: :custom1:
You must log in to submit a review. You can also log in or register using the form near the top of this page.