I don't have experience with JBoss on USS, but I have had some experience with Java on USS. If you haven't done so, you may want to get the JBoss source code from Source Forge and rebuild it on the USS platform. You might have to untar the configuration files on to an ASCII machines and ftp them to USS so that they go through an ASCII to EBCDIC conversion. The problem I had the most was regarding ASCII and EBCDIC conflict. Java Strings that are created at run time are EBCDIC byte encoded. If your JBoss implementation was built on an ASCII machine, it may contain static String types that were build using ASCII byte encoding. When at run time you try to compare these two Strings, the comparison will fail because the Strings contain different byte encoding.