As Mandrill shifts from free/cheap to expensive I went looking for an alternative. Enter the Sparkpost module.
But when I tried to use it with message_notify I began getting connection failures, apparently due to a newline character message_notify passes in the subject line. This is not a problem with Mandrill or with sending via mimemail or htmlmail.
Thanks to @zaporylie, there is now a patch at #2712857: Sanitize email subject → that sanitizes the message_notify header.
Closed: outdated
2.5
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