Grails Asynchronous Mail is a plugin for sending email messages asynchronously. It persists email messages to the database with Grails domain classes and sends them by a scheduled Quartz job. Mail is sent on a different thread, with the sendAsynchronousMail (or sendMail) method returning instantly, is not waiting for the mail to be actually sent. If the SMTP server isn't available, or other errors occur, the plugin can be set to retry later. The plugin depends on the quartz and the mail plugins. You also need a persistence provider plugin, hibernate4 and mongodb are supported.