[En-Nut-Discussion] Event API

[Matthias Ringwald]

>>> harald, will you add a critical section here?
>>> otherwise, I have to!
>>
>> I agree that it should be protected. Matthias,
>> you'd do me a favor if you do the change.
>>
> Task Accepted. Due soon..

I've added the critical section around the complete function body.
This leads to correct behavior.

Alternatively, after the comparison and the write, the critical section
might have been left, but I'm not sure if it would still be correct.
(To much thinking in the morning..)

Matthias