condition variable/semaphore/etc

[Howard Berkey]

Since D has the synchronized keyword in the language, implementing simple mutexes and/or critical sections are straightforward and trivial.  However, I have not found thus far any language (or phobos class) implementing something like a condition variable.

Am I just missing it?  It's certainly possible, as I am just now being able to dive down into D.  

CondVars (or, more easily, counting semaphores, which are useful in some situations that condvars are) are of course implementable by anyone based on a Mutex primitive, but it seems like they would be a good addition to the library.