It looks like your JAVA_HOME may not be set correctly. Java is not typically installed in /usr. What would typically happen on a *nix system would be that java has a link created in /usr/bin that points to the location of the actual java binary. The other java binaries (javac, jar, etc) may not have such links created which is why JAVA_HOME needs to be set to the actual path where Java is installed, e.g. /usr/java/jdk-1.6.0_25. I hope this helps get you on the right path.
File names on UNIX systems are case sensitive. Be sure the file name is exactly what the script is looking for.
I do not think it is causing this particular problem but one thing you should be aware of is that the only certified version of Java is 1.6.0-07. We have encountered errors during upgrades when we tried to use more recent versions. The errors disappeared when we backed up to the version specified in the release documentation.