This is the Visualization of Protein Ligand Graphs (VPLG) software package.
It includes several applications written in Java and Perl. See the doc/ subdirectory of the release for help with the programs.
VPLG was written by Tim Schaefer at the Molecular Bioinformatics Group of Ina Koch at Goethe-University Frankfurt, Germany. It has been re-written from scratch in Java, but is based and ideas by Ina Koch and Patrick May. See http://www.bioinformatik.uni-frankfurt.de for more information.
The official website for VPLG is at http://vplg.sourceforge.net. This is free software, published under GNU Public License 2.0.