http://bugs.kde.org/show_bug.cgi?id=121431

Actually there is something similar being worked on in branches/work/service-discovery. In nutshell it is generalization of zeroconf (actually its service discovery part) to use several protocols depending on what is needed. Already implemented (=good enough for testing) are zeroconf (for LANs), kopete plugin using \'magic\' messages (for Internet) and Lisa+portscan (mainly for testing, can be used on LAN).
Some notes about how should it work page
I\'m not exactly sure if it is not a solution to non-existant problem so please comment.