[Exim] regarding sender_verify and unsuccessful verification

hi,

just played a bit with sender_verify, and while doing so that upon
unsucccessful verification (played with a yahoo address as sender i
had problems with lately), i noticed exim telling in the debug log
that the address could not be verified, so "giving error after DATA".

question is what does it mean in terms of queueing and the like - is
the message coming in being written to disk then discarded, or is
it just piped to nirvana, just as if the recipient was :blackhole:'ed
?

thanks,

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