This document discusses how to automate testing of a web application that includes an email sending feature. It recommends using Black Jumbo Dog, an open source desktop application that can act as an SMTP server. Black Jumbo Dog exposes a web API that allows test code to control the SMTP server, clean up received emails, and retrieve emails to validate contents. The test code would communicate with Black Jumbo Dog via its web API while also interacting with the web application using a tool like Selenium.