Concurrency in D and Active Objects

[Yigal Chripun]

Active Objects were mentioned in a thread on the NG, so I've looked
around and found the following file which explains the idea in a very
clear way. it also outline a possible implementation for C#.

http://blog.gurock.com/wp-content/uploads/2008/01/activeobjects.pdf

Since D is way better than Java/C#/C++ (all mentioned in the above
article) it seems to me that such a useful abstraction could be
implemented in D and probably would be simpler to do that than the other
languages mentioned above.

What are the benefits of D's approach of implementing a functional
subset with pure functions compared to the above abstraction of Active
Objects?
Also, to make D's functional subset run Concurrently doesn't D need a
special runtime that parallelizes the code (which D currently doesn't have)?

--Yigal