How to use momo-src.jar momo-src.jar is the Java archive file which contains all Java source files and relevant data files, as well as a Geant4.9.4 example in ./MomoHome directory. If you use MOMO.jar to run MOMO, momo-src.jar isn't necessary. When you have new JDK or other JDK like OpenJDK etc, momo-src.jar can be used to create your own MOMO.jar. The required tools are 1) JDK-1.6 or later (OpenJDK isn't tested fully) 2) Apache ant (1.7 or later) To compile, 1) copy momo-src.jar to any clean directory and change directory to there 2) jar fvx momo-src.jar and you have the full codes and data. 3) ant (build.xml is use by default) and you have MOMO.jar the executable MOMO jar file 4) java -jar ./MOMO.jar you may have a warning on the unsecure use of the HashTable but you can neglect it.