This is Idbg, an IJVM execution environment and debugger. To compile it, run the commands: ./configure; make Assuming they execute sucessfully, you'll have an idbg binary in src. It can be run from there, or you can install it by running make install For optimal use, idbg should be used in conjunction with version 1.0d or higher of ijvmasm from the mic1 distribution, available from . 1.0d includes debug symbol generation support, and it fixes a bug with the code generation. When ijvmasm is invoked with 3 arguments, the third is the debugging symbols file. (This isn't yet documented in mic1.) Idbg can then be called with the ijvm file and the symbols file. For example: java ijvmasm add.jas add.ijvm add.idbg idbg add.ijvm add.idbg Idbg can be called without a symbols file, but it loses a bit of functionality when used that way. The files idbg.txt and idbg.html contain information on how to use idbg once it's running. Comments are welcome. Tom Rothamel