config.action_mailer.smtp_settings = {
  address: "smtp.gmail.com",
  port: 587,
  domain: ENV["GMAIL_DOMAIN"],
  authentication: "plain",
  enable_starttls_auto: true,
  user_name: ENV["GMAIL_USERNAME"],
  password: ENV["GMAIL_PASSWORD"]
}


LINUX:

~/.pam_environment

export GMAIL_USERNAME=noreplay@ernanesena.com.br
export GMAIL_PASSWORD=cliente2011
export GMAIL_DOMAIN=ernanesena.com.br