Source code for this has been floating around for a while, but I've never seen a compiled / signed version anywhere. So I built it. Signed with the dktest/dntest/ditest from Andrew de Quincy. Should be part of the (standard?) merged keystore already.
Sadly, this viewer lacks support for annotations in PGN. That means no alternate moves, no commentary, not even ! / ? move ratings. I pulled several pgn archives and stripped them of comments, please see (the other) attached zip if you need something to play.
The source distribution includes pgnparse, a Java pgn parser, which may be out of date... I tried to update it but too much Java 1.5-specific code is used in the new version.
If you want to built it yourself, here's the source URL:
Depends on KWT (but a .jar is included in lib/)
adq's keystore, in the ktest download:
A fair bit of hacking around in build.xml is needed to make this thing build against KWT instead of KDK. Best of luck.