Shoutbox

Yep, but lets stick to the facts: there aren't any accurate statistics about the number of Esperanto speakers, simply because it's way too simple to learn and anyone can, thus there no way to control how many people will speak it.
Second, no country has set it as official language, wich leads to Esperanto will always be a second+ language.

Now, about the languages in Messenger Plus!: all them are based on user statiscs. If a language has as many users as required, it will be included in the setup, as was Greek some time ago. If Esperanto isn't officially included in the setup, means there aren't as many users as required. As simple as it can be. =)