# the monkey punch
module Merb
  class Mailer
    class_eval("def net_smtp
      ver = config[:cert_verify] || OpenSSL::SSL::VERIFY_PEER
      Net::SMTP.enable_tls(ver) if config[:use_tls]
      Net::SMTP.start(config[:host], config[:port].to_i, config[:domain],
      config[:user], config[:pass], config[:auth]) do |smtp|
        smtp.send_message(@mail.to_s, @mail.from.first, @mail.to.to_s.split(/[,;]/))
      end
    end")
  end
end

#in merb_init.rb
Merb::Mailer.config = {
    :host=>'smtp.example.com',
    :port=>'587',
    :user=>'appemailaccount@example.com',
    :pass=>'passwd',
    :auth=>:plain,
    :use_tls => true,
    :cert_verify => OpenSSL::SSL::VERIFY_NONE
    # see OpenSSL::SSL & Net::SMTP (via tlsmail gem) for more info on this
}

# send mail as normal