Description:
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When mlmmj unsubscribes a person due to bouncing, following is noted in the 
operations log:

mlmmj-maintd: email@address.com unsubscribed due to bouncing since  Tue Aug  9 
16:42:57 2011

But in my case, the address was not removed from the subscribers file. The 
permission on these files were such, that mlmmj could not modify them.

I would expect mlmmj to complain or log an error somewhere, if it can not modify 
the subscriber file in question.

From the operations log it looks like the subscriber was removed just fine. But 
he was not.

I don't know if this is a general missing validation or function return check, 
or if it's just in this case (wrong permissions).

Test script:
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Set permission such that mlmmj can not modify the subscribers file, make an address unsubscribe due to bouncing - see error logs says he was unsubscribed - see that subscriber is still in subscribers file.

Expected result:
----------------
An error message, that mlmmj could not remove the subscriber due to file 
permission errors.

Actual result:
--------------
Error log says subscriber was removed, when in fact he was not.