I have a very strange search result....
While on Linux (Ubuntu) with jdk 5.0, no root device is found, on Ms Windows (also jdk 5.0) the program can find all devices on my Network. Also the examples cannnot be found neigher on localhost nor on another PC. Since other programs (like ktorrent) does not have any problems communicating with my UPNP devices, I don't know where to start looking.
I etherealed the communication, but there was none. This means no SSDP made its way to the network interface.