For portable system I would not hard code path to sendmail binary. First of all most (I've seen) systems (several Linux distros and FreeBSD) use /usr/sbin/sendmail by default. Probably using SMTP would be more portable (it is quite safe to use Net::SMTP since libnet is popular enough to be installed on most systems).

But of course it is better to put such things in config.

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Ilya Martynov (http://martynov.org/)