Facebook Chat XMPP Services

Since 2 months ago, I’ve got my second remote job as Java EE Developer for Telco Company in Singapore named Hub9. So, currently now I’m working for two Telco’s Company in Singapore (i.e. CoreSDP and Hub9) as Java EE Developer. Both of them are remote jobs (which means working from home :-D), and I’ve got monthly payment for these jobs. This is what i’ve been dreaming for a long time :-).
Start from here I’ll write some notes about anything what i’ve been doing for over the last 2 months with Hub9.
As my first assignment, they’ve asked me to develop facebook chat (IM/Instant Messaging) application via SMS (known as Facebook SMS Chat). As you’ve already known, there are many chat (IM) application now, such as Yahoo Messenger, GoogleTalk, eBuddy, Jabber, etc. Even Facebook has provided it’s application with IM service, so every user on facebook could have a conversation via this chat (IM) service.
Every IM service need communication protocol in order to be working correctly. There are many protocols around can be used for this purpose. Some of them are under commercial (propietary) license, and some of them are not (means ‘free’, and this is what i’m going to use :-D).
One of the protocol that is free to be used is XMPP.
XMPP (stands for eXtensible Messaging and Presence Protocol) is an open-standard communication protocol for message oriented middleware based on XML (eXtensible Markup Language). This protocol was originally named Jabber, and was developed by the Jabber open source community in 1999 for near real-time, extensible instant messaging (IM), presence information, and contact list maintenance. The software implementation and client application based on this protocol are distributed as free and open source software (looks nice to me ^_^).
I think, you should read by your self later about XMPP, so I won’t give you the detail explanation about XMPP here (b’cause I’m not the kind of person who’s enjoy to talking to much about the ‘philosophy’ behind the ‘theory’ #:-s). So please googling or read the “RTFM” :-).
One thing that I think is important for us to know before we jump into the XMPP implementation is: basically, there are 2 implementations of XMPP. i.e. XMPP Server and XMPP Client.

In order to work, we should have those 2 implementation in our software.