Mutexes and locking

[alexhairyman]

I think I'm missing something big, but I'm having troubles with 
mutexes (using in a parallel foreach loop somewhere else); Why do 
the trylocks return true shouldn't they return false because the 
mutex is already locked? I don't think this is a phobos bug, I'm 
on OSX using dmd 2.065

import core.sync.mutex;
import std.stdio;

void main()
{
   Mutex m = new Mutex;
   m.lock();
   writefln("%s", m.tryLock());
   writefln("%s", m.tryLock());
   return;
}

produces:
true
true

Thanks!
   Alex