Jolly Brisk!™ has a simply marvellous design, making it the natural choice for chats with one's chums and pals. "Res ipsa loquitur" as my old tutor was wont to say.
Splendid!™ is a robust and high-quality C++ library for implementing those tricky little XMPP applications. It's compliant with all of the relevant standards thought up by those frightfully clever chaps and chapesses at the IETF and XSF. Rather!
Super!™ Java SDK
Super!™ is a native Java (no JNI) port of the Splendid!™ C++ library by golly! After discussing it over dinner, followed by several brandies and a cigar, we decided it would be quite a wheeze to license Super!™ under the GNU General Public License.