I finally found the time to fiddle around with an old Linux box (with java 1.4.2 installed) to check if things where working like they should ... and they didn't.
Because I only used classes and libraries fit for 1.4, I expected everything to work in 1.4 even though I wrote the app in 1.5 (and didn't test it in 1.4
). Some of the methods methods didn't exist in 1.4 though (like string.format), and those where easy to fix.
So here's a version identical to the 1.3 from earlier, except from some internal changes to work in java 1.4.2. This version also definately works in Linux (well, it does on my old Mandriva 2005 pc).