/* Sending mail with default mailSender */
sendMail {
    to "someoneelse@somewhere.com"
    subject "Hello Someone"
    body 'From default mailSender'
}

/* Sending mail with custom mailSender */
MailSender mailSender = new JavaMailSenderImpl()
mailSender.host = "smtp.somemailprovider.com"
mailSender.port = 465
mailSender.username = "someone@somewhere.com"
mailSender.password = "somepassword"
mailSender.javaMailProperties = ["some":"properties"]
sendMail(mailSender) {
    to "someoneelse@somewhereelse.com"
    subject "Hello Someone Else"
    body 'From custom mailSender'
}