[plt-scheme] Uniqueness of dead-evt

Hello,

Is the event returned by thread-dead-evt guaranteed to be eq? to the
event returned by any future calls to thread-dead-evt with the same
thread?

I.e. Can I count on this?:

-> (define t (thread (lambda () (sync (make-semaphore)))))
-> t
#<thread>
-> (eq? (thread-dead-evt t) (thread-dead-evt t))
#t

Thanks,
N.