We use gnu.bytecode from the kawa scheme compiler for this. http://www.gnu.org/software/kawa/gnu.bytecode/
Run this command to download it then ant to compile it. This gives you kawa.jar which includes gnu.bytecode. It's needed when assembling .class files but the files we create are freestanding.
svn -q checkout svn://sourceware.org/svn/kawa/trunk kawa