>The problem is...javax.jnlp isn't included in the JDK (docs).
Yea, well you need that webstart toolkit
>This seems strange, since I would have thought that the
>packaging system for the main way of distributing apps
>would be considered a core part of the JDK!
No, it's not strange.
It's silly. The jnlp jar needed for compilation is... behold... a whopping 7 kilo bytes in size

Well, that toolkit thingy is somewhere over at suns page (oh oh). Stumbled upon it somewhat accidently. Actively searched for it 2 weeks ago and was unable to find it... aw... I hate the structure of sun's pages.
Btw that jnlp.jar is only needed for compilation. You don't need to include it into your distribution (because webstart has that classes... uhm...

)
@misterX
>but in the same time, it looks extraordinary complex!
Indeed it is. I guess it makes sense to wrap up that stuff a bit, because it usually doesn't matter *where* it fails - just if.