I've heard that happens in D, too. You can still call C functions at your peril, and no people complained so far.
I believe D (DMD, at least) is in the exact same situation as C is as far as the stack goes. There is some code in the garbage collector to get the bounds of each thread's stack, but that's it, I think.
-- Best regards, Vladimir mailto:vladi...@thecybershadow.net