OK. So something means you need to run a .jnlp file provided by some site or other. Suddenly we’re in the world of Java pain.
Ubuntu’s OpenJDK is a second class citizen – and we’re supposed to install Sun/Oracle’s version of Java. And Oracle being what they this means they’ve made it difficult – possible – but why should Oracle make me have to install via downloaded tarballs etc.
Good news. Ubuntu’s OpenJDK Java 7 Runtime seems to do the job. Also tick the Web Browser plugin option. Then – Firefox will offer Icetea as the option to run the jnlp file.
I had installed Xubuntu-restricted-extras – and added the Canonical partners to the repository list. And now the server console provided by http://www.hetzner.de works – yay!