What can I do with the source?

Don't forget to read the license carefully. It explains in detail what you can and cannot do.

To make it short, you can pretty much do whatever you want - as long as we get some acknowledgment. You can distribute it in binary or source form, take all or part of it and put it in something else, and then redistribute it. It's all up to you.

However, IBM retains control of the names "IBM" and "Jikes^TM". You can't use them without our permission.

You are under no obligation to tell us what you are doing with the source, or to inform us of any changes you make.