Question to TC re: versions

I have received a request for info about whether a compliant
XACML 2.0 engine has any requirements to explicitly support
XACML 1.1 or XACML 1.0.

I expect the answer is no, but just want to determine if there
are any known reqts in this area. I have checked the core
spec and aside from an entry in the list of references for
xacml 1.0 and 1.1, there are no additional refs I could find
in the core document.

Any advice would be much appreciated.

    Thanks,
    Rich