building Dovecot in Debian 9

[Peter van der Does]

Kevin,

Regarding the configuration error, your missing a package:
zlib1g-dev

As far as the deprecation warning, it's a bit more complicated. The
source of Dovecot needs to be patched to check for the OpenSSL version
and depending on the version use a different DH_generate_numbers function.

Regards,

Peter

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