Open source alternative to DITA Open Toolkit

Question

I'm working on a web app that will need to process DITA documents from persistent storage (likely a JCR). The DITA Open Toolkit is the only DITA implementation I'm aware of, but it requires all of your documents to exist on the filesystem. Ideally, I'd like something that works like the DITA OT, but allows you to provide a resolver (much like an XSLT URIResolver) to pull referenced content from other sources.

If people have other ideas, such as using a virtual filesystem to trick the DITA OT into working, I'd love to hear those too. Thanks!

Edit: I forgot to mention in the original post that I'm looking for an open-source solution, as this is for a project released under the Educational Community License.

Answer 1

After some evaluation, the newest version of the XMLMind Dita Converter (ditac) is really up to the job. Performance is at least double that of the Open Toolkit for building identical projects: http://www.xmlmind.com/ditac/

Answer 2

One thing to note about XMLMind Dita Converter (ditac) is that it's released under the Mozilla Public License, which according to http://www.gnu.org/licenses/license-list.html#GPLIncompatibleLicenses is not compatible with GPL.