Brian, thanks for the explanation. I am glad that you are open to making modifications to the OSS codebase rather than reinventing something.
Let me think more on what you said.
XACML is what brings in the attribute based authorization to the Java EE specification.
We can certainly discuss ways by which we can mutually get at a common ground.
Please go ahead and give some detailed description if you have and I should be able to see where we can adapt/change our codebase to achieve the goals. In the end, we both benefit. :)