Weird things in the mail queue

Aki Tuomi aki.tuomi at
Thu Feb 21 13:55:28 EET 2019

On 21.2.2019 13.47, Lionel Elie Mamane via dovecot wrote:
> I noticed a mail stuck in my mail queue. dovecot-lda was returning
> error 64 Invalid parameter given. (EX_USAGE).
> Weird, weird, weird. After some sleuthing, I found the sender address
> was FirstLast at domain.tld, with a UTF8-encoded Unicode U+FEFF ZERO
> WIDTH NO-BREAK SPACE character (AKA byte order mark) between "First"
> and "Last" :)
> Since that is passed as the -f parameter to dovecot-lda, it was giving
> the 64 error.

Your MTA should not be passing this along.


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