Making your app connect to random SMTP servers every time it needs to validate an email address doesn't seem like a good idea.
Shared domains (gmail.com etc.) might even get you blacklisted if you flood the same SMTP servers over and over again.
Shared domains (gmail.com etc.) might even get you blacklisted if you flood the same SMTP servers over and over again.
The simple work around - don't do it. This code is susceptible to Denial of Service problems similar to the URLField verify_exists option https://www.djangoproject.com/weblog/2011/sep/09/security-re... - a malicious SMTP server could tarpit all your SMTP connections from Django leaving your site with no workers to process other requests.
The email validation from an EmailField is designed to ensure that it could be a valid email address, not that it's a valid mailbox. Live with the limitation instead of trying to be too smart.