title: Suspicious sign in prevented (Heroku, Amazon AWS, Gmail SMTP)
body: <p>I occasionally receive emails from Google (<code>accounts-noreply@google.com</code>), similar to the following:</p>
  
  <pre><code>Subject: Suspicious sign in prevented
  
  Someone recently tried to use an application to sign in to your Google  
  Account, ________@gmail.com. We prevented the sign-in attempt in case  
  this was a hijacker trying to access your account. Please review the  
  details of the sign-in attempt:
  
  Monday, November 19, 2012 8:40:55 PM GMT
  IP Address: 184.72.161.49 (amazonaws.com)
  Location: Dixmoor, IL, USA
  
  If you do not recognize this sign-in attempt, someone else might be trying  
  to access your account. You should sign in to your account and reset your  
  password immediately. Find out how at  
  http://support.google.com/accounts?p=reset_pw
  
  If this was you, and you want to give this application access to your  
  account, complete the troubleshooting steps listed at  
  http://support.google.com/mail?p=client_login
  
  Sincerely,
  The Google Accounts Team
  
  
  © 2012 Google Inc. 1600 Amphitheatre Parkway, Mountain View, CA 94043
  
  You have received this mandatory email service announcement to update you  
  about important changes to your Google product or account.
  </code></pre>
  
  <p>Indeed, this was me, as I have an app running on <strong>Heroku</strong> (hence why the IP address is from <code>amazonaws.com</code>), and I send email directly from my app via Gmail SMTP (I don't think it should matter, but specifically, I'm using the <a href="https://github.com/adamwiggins/gmail_smtp" rel="noreferrer">gmail_smtp plugin</a> which I <a href="http://code.coneybeare.net/how-to-convert-simple-rails-23-style-plugins" rel="noreferrer">updated for Rails 3.2</a>).</p>
  
  <p>Is there a way to avoid this warning, or a way to whitelist known IPs?</p>