We have 50+ Java batch processes that run at different times of the day. They run on a Solaris box, and are started via cron. Currently, the only way we only know if they succeed or fail is by an email generated at the end of each batch process. We have a support team that monitors these emails. Recently, we've had issues with emails not being received, even though the batches are running. There must be a better way.

Without having to reinvent the wheel, are there any open source batch monitoring applications?

And a more general question, what is the best way to monitor batch processes?