Obviously DataNucleus is open source software so your team could, in principle, look through the code and debug problems and/or develop new features. Often though you don't have the time to devote to such activities so would prefer to out source this aspect of your project. We provide for such a situation, and since we wrote the software in the first place, nobody is better equipped to resolve problems and get your project moving forward. DataNucleus can provide a level of support to meet your requirements, and rather than having fixed off-the-shelf arrangements we prefer to tailor them to your needs. In addition we can provide consulting on specific areas of data persistence whether that is on-site, or time-based via Skype/email/IRC. It should be noted that DataNucleus support is offered by the likes of OpenLogic. They do not have access to DataNucleus committers (or the ability to update DataNucleus), nor extensive DataNucleus experience, and that aside they charge a lot more for such support than what we do. You cannot get better value and a higher level of DataNucleus experience than from us.
In addition to help addressing particular problems/features, we also cater for getting your team up-to-speed on the various data persistence technologies, and the specifics of using DataNucleus. This can often reap rewards later in that your engineers can hit the ground running, and have a basic persistence capability in a very short space of time. This training is similarly structured to meet your requirements, focussing on the datastore that you have chosen for your project.
We look forward to working with you