Unity4 & sgen GarbageCollector

Does Unity 4 using Mono 2.8.2 enable generational garbage collector (sgen) or it’s still using Boehm collector?

If Boehm, how I can activate sgen GC?

And will it work for iOS?

sorry my english

Belated reply but in case anyone else comes across this: At this time unfortunately you’re stuck with Boehm.