Psi

From iA wiki

See also: Instant Messengers | Jabber

Psi | Sourceforge Page

A Windows, MacOS X and Linux (QT) GPLed client which uses the Jabber network to be multi-network. It also has an interesting multi-language feature:

"Psi has full support for Unicode. Unicode allows Psi to send and receive messages in other languages, even ones that aren't based upon the English letterset. In fact, you are able to use Psi in your choice of eight different languages, with more on the way! "

More about Psi

PSI also allows for secure communications via SSL. It has not yet been tested if this works with other Jabber clients or merely PSI.