XACML and Constrained RBAC

Hi all,

I am mostly aware of the scientific literature about XACML and its extensions 
(both architecturally and syntactically) for Constrained RBAC. However, is there 
any XACML implementation (i.e. PDP, PEP etc) that supports for instance

Dynamic Separation of Duty (DSoD) out of box and perhaps accessible somehow?
Thanks in advance.

-- 
Fatih Turkmen
Web: http://sites.google.com/site/fturkmen/