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Why does the autoresponse have to come from an unread email account?

For RIPE DBM we do this to avoid mail loops (I think - Oleg knows more about these mysteries than I do).

ah, right! loops should indeed be avoided in automated response systems, mail servers could quickly come to a grinding halt. (IIRC, NCC has had it's shares of loop problems with the hostmaster robot in the past)

For hostmasters, the "From:" is actually <hostmaster@ripe.net>. I guess it makes sense for the "From:" to be <ris@ripe.net> in this case.

If it cannot create loops, from (or reply-to for that matter) <ris@ripe.net> would be great for tickets coming in to ris. -- Rene