Description:
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When a mail is sent to a recipient address that contains a + and the list address in that order, mlmmj interprets the left part after the + as a command although the right part is not the list name.


Test script:
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Ex: send a mail to: someone+ext@domain1.net, listname@domain2.net

The first address is not the list address but in function main, recipextra is computed from the first email address:
  recipextra = recipient_extra(listdir, toemails.emaillist[0]);
and function recipient_extra doesn't check that the left part "someone" is not the list name. So "ext" is considered as an unknown command and the mail is silently discarded.


Expected result:
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mlmmj should check that the left part of the first address is the listname before considering the right part as a command.